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Abstract:

An ethylenic polymer comprising amyl groups from about 0.1 to about 2.0
units per 1000 carbon atoms as determined by Nuclear Magnetic Resonance
and both a peak melting temperature, Tm, in ° C., and a heat
of fusion, Hf, in J/g, as determined by DSC Crystallinity, where the
numerical values of Tm and Hf correspond to the relationship
Tm≧(0.2143*Hf)+79.643. An ethylenic polymer comprising
at least one preparative TREF fraction that elutes at 95° C. or
greater using a Preparative Temperature Rising Elution Fractionation
method, where at least one preparative TREF fraction that elutes at
95° C. or greater has a gpcBR value greater than 0.05 and less
than 5 as determined by gpcBR Branching Index by 3D-GPC, and where at
least 5% of the ethylenic polymer elutes at a temperature of 95°
C. or greater based upon the total weight of the ethylenic polymer.

Claims:

1-20. (canceled)

21. An ethylenic polymer comprising at least one preparative TREF
fraction that elutes at 95.degree. C. or greater using a Preparative
Temperature Rising Elution Fractionation method, where at least one
preparative TREF fraction that elutes at 95.degree. C. or greater has a
branching level greater than about 2 methyls per 1000 carbon atoms as
determined by Methyls per 1000 Carbons Determination on P-TREF Fractions,
and where at least 5 weight percent of the ethylenic polymer elutes at a
temperature of 95.degree. C. or greater based upon the total weight of
the ethylenic polymer.

22. An ethylenic polymer comprising at least one preparative TREF
fraction that elutes at 95.degree. C. or greater using a Preparative
Temperature Rising Elution Fractionation method, where at least one
preparative TREF fraction that elutes at 95.degree. C. or greater has a
g' value of less than 1 as determined by g' by 3D-GPC, and where at least
5 weight percent of the ethylenic polymer elutes at a temperature of
95.degree. C. or greater based upon the total weight of the ethylenic
polymer.

23. The ethylenic polymer of claim 22, where the g' value is less than
0.95.

24. A process, comprising: A) polymerizing ethylene in the presence of a
catalyst to form a linear ethylene-based polymer having a crystallinity
of at least 50% as determined by DSC Crystallinity in a first reactor or
a first part of a multi-part reactor; and B) reacting the linear
ethylene-based polymer with additional ethylene in the presence of a
free-radical initiator to form an ethylenic polymer in at least one other
reactor or a later part of a multi-part reactor.

25. The process of claim 24, where the reaction of step (B) occurs by
graft polymerization.

26. The process of claim 24, where the catalyst of step (A) is a
metallocene catalyst.

27. The process of claim 26, where polar compounds, if present in the
first reactor or the first part of a multi-part reactor, do not inhibit
the activity of the metallocene catalyst.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the priority benefit under 35 USC
§119(e) to U.S. Provisional Patent Application No. 61/036,329, filed
Mar. 13, 2008, the disclosure of which is incorporated herein by
reference.

BACKGROUND OF THE INVENTION

[0002] There are many types of polyethylene made and sold today. Two types
in particular are made by various suppliers and sold in large quantities.
These two types are linear low density polyethylene (LLDPE) and high
pressure free radical polyethylene (usually called LDPE). Sometimes
polymer users blend these two types of polyethylene together to try to
modify properties such as flowability or processability. However, this
blending can also bring deficiencies in other physical properties. Thus,
it would be advantageous to have similar mechanical properties to LLDPE
and also the processability similar to that of LDPE.

[0003] We have now discovered new polymers which have the performance
attributes of both LLDPE and LDPE.

SUMMARY OF THE INVENTION

[0004] In one embodiment, an ethylenic polymer is claimed comprising at
least 0.1 amyl branches per 1000 carbon atoms as determined by Nuclear
Magnetic Resonance and both a highest peak melting temperature, Tm,
in ° C., and a heat of fusion, Hf, in J/g, as determined by
DSC Crystallinity, where the numerical values of Tm and Hf
correspond to the relationship:

Tm≧(0.2143*Hf)+79.643, preferably
Tm≧(0.2143*Hf)+81

and wherein the ethylenic polymer has less than about 1 mole percent
hexene comonomer, and less than about 0.5 mole percent butene, pentene,
or octene comonomer, preferably less than about 0.1 mole percent butene,
pentene, or octene comonomer.

[0005] The ethylenic polymer can have a heat of fusion of the ethylenic
polymer of less than about 170 J/g and/or a peak melting temperature of
the ethylenic polymer of less than 126° C. Preferably the
ethylenic polymer comprises no appreciable methyl and/or propyl branches
as determined by Nuclear Magnetic Resonance. The ethylenic polymer
preferably comprises no greater than 2.0 units of amyl groups per 1000
carbon atoms as determined by Nuclear Magnetic Resonance.

[0006] In another embodiment, an ethylenic polymer is claimed comprising
at least one preparative TREF fraction that elutes at 95° C. or
greater using a Preparative Temperature Rising Elution Fractionation
method, where at least one preparative TREF fraction that elutes at
95° C. or greater has a branching level greater than about 2
methyls per 1000 carbon atoms as determined by Methyls per 1000 Carbons
Determination on P-TREF Fractions, and where at least 5 weight percent of
the ethylenic polymer elutes at a temperature of 95° C. or greater
based upon the total weight of the ethylenic polymer.

[0007] In a third embodiment, an ethylenic polymer is claimed comprising
at least one preparative TREF fraction that elutes at 95° C. or
greater using a Preparative Temperature Rising Elution Fractionation
method, where at least one preparative TREF fraction that elutes at
95° C. or greater has a g' value of less than 1, preferably less
than 0.95, as determined by g' by 3D-GPC, and where at least 5 weight
percent of the ethylenic polymer elutes at a temperature of 95° C.
or greater based upon the total weight of the ethylenic polymer.

[0008] In a fourth embodiment, an ethylenic polymer is claimed comprising
at least one preparative TREF fraction that elutes at 95° C. or
greater using a Preparative Temperature Rising Elution Fractionation
method, where at least one preparative TREF fraction that elutes at
95° C. or greater has a gpcBR value greater than 0.05 and less
than 5 as determined by gpcBR Branching Index by 3D-GPC, and where at
least 5 weight percent of the ethylenic polymer elutes at a temperature
of 95° C. or greater based upon the total weight of the ethylenic
polymer.

[0009] In a fifth embodiment, an ethylenic polymer is claimed comprising
at least one preparative TREF fraction that elutes at 90° C. or
greater using a Preparative Temperature Rising Elution Fractionation
method, where at least one preparative TREF fraction that elutes at
90° C. or greater has a branching level greater than about 2
methyls per 1000 carbon atoms as determined by Methyls per 1000 Carbons
Determination on P-TREF Fractions, and where at least 7.5 weight percent
of the ethylenic polymer elutes at a temperature of 90° C. or
greater based upon the total weight of the ethylenic polymer.

[0010] In a sixth embodiment, an ethylenic polymer is claimed comprising
at least one preparative TREF fraction that elutes at 90° C. or
greater using a Preparative Temperature Rising Elution Fractionation
method, where at least one preparative TREF fraction that elutes at
90° C. or greater has a g' value of less than 1, preferably less
than 0.95, as determined by g' by 3D-GPC, and where at least 7.5 weight
percent of the ethylenic polymer elutes at a temperature of 90° C.
or greater based upon the total weight of the ethylenic polymer.

[0011] In a seventh embodiment, an ethylenic polymer is claimed comprising
at least one preparative TREF fraction that elutes at 90° C. or
greater using a Preparative Temperature Rising Elution Fractionation
method, where at least one preparative TREF fraction that elutes at
90° C. or greater has a gpcBR value greater than 0.05 and less
than 5 as determined by gpcBR Branching Index by 3D-GPC, and where at
least 7.5 weight percent of the ethylenic polymer elutes at a temperature
of 90° C. or greater based upon the total weight of the ethylenic
polymer.

[0012] Finally, a process for making such ethylenic polymers is claimed,
said process comprising: [0013] A) polymerizing ethylene in the
presence of a catalyst to form a linear ethylene-based polymer having a
crystallinity of at least 50% as determined by DSC Crystallinity in a
first reactor or a first part of a multi-part reactor; and [0014] B)
reacting the linear ethylene-based polymer with additional ethylene in
the presence of a free-radical initiator to form an ethylenic polymer in
at least one other reactor or a later part of a multi-part reactor.

[0016] Also preferably, the catalyst of step (A) can be a metallocene
catalyst. If polar compounds are present in the reaction process, such as
being present in the first reactor or the first part of a multi-part
reactor, such polar compounds do not inhibit the activity of the
metallocene catalyst.

DESCRIPTION OF THE DRAWINGS

[0017] The foregoing summary as well as the following detailed description
will be better understood when read in conjunction with the appended
drawings. It should be understood, however, that the invention is not
limited to the precise arrangements and instrumentalities shown. The
components in the drawings are not necessarily to scale, with emphasis
instead being placed upon clearly illustrating the principles of the
present invention. Moreover, in the drawings, like reference numerals
designate corresponding parts throughout the several views.

[0018] FIGS. 1A-D are schematics illustrating the steps of formation of
the inventive ethylenic polymer 400 from a linear ethylene-based polymer
100.

[0019]FIG. 2 is a plot of a relationship between density and heat of
fusion for 30 Commercially Available Resins of low density polyethylene
(LDPE).

[0024]FIG. 7 is a plot of maximum peak melting temperature versus heat of
fusion for Examples 1-5, Comparative Examples 1 and 2, and Commercially
Available Resins 1-30, and a linear demarcation between the Examples, the
Comparative Examples, and the Commercially Available Resins.

[0028]FIG. 11 is a plot of methyls per 1000 carbons (corrected for chain
ends) versus weight average elution temperature as determined by Methyls
per 1000 Carbons Determination on P-TREF Fractions analysis of Fractions
AB and CD for Examples 3-5.

[0029]FIG. 12 represents a schematic of a cross-fractionation instrument
for performing Cross-Fractionation by TREF analysis.

[0031] The following discussion is presented to enable a person skilled in
the art to make and use the disclosed compositions and methods. The
general principles described may be applied to embodiments and
applications other than those detailed without departing from the spirit
and scope of the disclosed compositions and methods. The disclosed
compositions and methods are not intended to be limited to the
embodiments shown, but is to be accorded the widest scope consistent with
the principles and features disclosed.

[0032] Currently, when a high crystallinity, ethylene-based polymer is
used with a low crystallinity, highly long chain branched ethylene-based
polymer, there is no mechanical means to create a blend that faithfully
combines all the physical performance advantages of the ethylene-based
polymer with the all the favorable processing characteristics of the
highly long chain branched ethylene-based polymer. Disclosed are
compositions and methods that address this shortcoming.

[0033] In order to achieve an improvement of physical properties over and
above a mere physical blend of a ethylene-based polymer with a highly
branched ethylene-based polymer, it was found that bonding the two
separate constituents--an ethylene-based polymer and a highly long chain
branched ethylene-based polymer--results in an ethylenic polymer material
with physical properties akin to or better than the ethylene-based
polymer component while maintaining processability characteristics akin
to the highly long chain branched ethylene-based polymer component. It is
believed that the disclosed ethylenic polymer structure is comprised of
highly branched ethylene-based polymer substituents grafted to or
free-radical polymerization generated ethylene-based long chain polymer
branches originating from a radicalized site on the ethylene-based
polymer. The disclosed composition is an ethylenic polymer comprised of
an ethylene-based polymer with long chain branches of highly long chain
branched ethylene-based polymer.

[0034] The combination of physical and processing properties for the
disclosed ethylenic polymer is not observed in mere blends of
ethylene-based polymers with highly long chain branched ethylene-based
polymers. The unique chemical structure of the disclosed ethylenic
polymer is advantageous as the ethylene-based polymer and the highly long
chain branched ethylene-based polymer substituent are linked. When
bonded, the two different crystallinity materials produce a polymer
material different than a mere blend of the constituents. The combination
of two different sets of branching and crystallinity materials results in
an ethylenic polymer with physical properties that are better than the
highly long chain branched ethylene-based polymer and better
processability than the ethylene-based polymer.

[0035] The melt index of the disclosed ethylenic polymer may be from about
0.01 to about 1000 g/10 minutes, as measured by ASTM 1238-04 (2.16 kg and
190° C.).

[0038] Suitable heterogeneous linear ethylene-based polymers include
linear low density polyethylene (LLDPE), ultra low density polyethylene
(ULDPE), and very low density polyethylene (VLDPE). For example, some
interpolymers produced using a Ziegler-Natta catalyst have a density of
about 0.89 to about 0.94 g/cm3 and have a melt index (I2) from
about 0.01 to about 1,000 g/10 minutes, as measured by ASTM 1238-04 (2.16
kg and 190° C.). Preferably, the melt index (I2) is from
about 0.1 to about 50 g/10 minutes. Heterogeneous linear ethylene-based
polymers may have a molecular weight distributions, Mw/Mn, from
about 3.5 to about 4.5.

[0039] The linear ethylene-based polymer may comprise units derived from
one or more α-olefin copolymers as long as there is at least 50
mole percent polymerized ethylene monomer in the polymer.

[0040] High density polyethylene (HDPE) may have a density in the range of
about 0.94 to about 0.97 g/cm3. HDPE is typically a homopolymer of
ethylene or an interpolymer of ethylene and low levels of one or more
α-olefin copolymers. HDPE contains relatively few branch chains
relative to the various copolymers of ethylene and one or more
α-olefin copolymers. HDPE can be comprised of less than 5 mole % of
the units derived from one or more α-olefin comonomers

[0041] Linear ethylene-based polymers such as linear low density
polyethylene and ultra low density polyethylene (ULDPE) are characterized
by an absence of long chain branching, in contrast to conventional low
crystallinity, highly branched ethylene-based polymers such as LDPE.
Heterogeneous linear ethylene-based polymers such as LLDPE can be
prepared via solution, slurry, or gas phase polymerization of ethylene
and one or more α-olefin comonomers in the presence of a
Ziegler-Natta catalyst, by processes such as are disclosed in U.S. Pat.
No. 4,076,698 (Anderson, et al.). Relevant discussions of both of these
classes of materials, and their methods of preparation are found in U.S.
Pat. No. 4,950,541 (Tabor, et al.).

[0043] A copolymer may incoporate an α,ω-olefin comonomer.
Examples of straight-chain or branched acyclic diene compounds that may
be used as an α,ω-olefin comonomer include 1,6-heptadiene,
1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1,11-dodecadiene,
1,13-tetradecadiene, and lower alkyl substituted derivatives thereof;
examples of the monocyclic alicyclic diene compounds include
1,3-divinylcyclopentane, 1,2-divinylcyclohexane, 1,3-divinylcyclohexane,
1,4-divinylcyclohexane, 1,5-divinylcyclooctane,
1-allyl-4-vinylcyclohexane, 1,4-diallylcyclohexane,
1-allyl-5-vinyl-cyclooctane, 1,5-diallylcyclooctane, and lower alkyl
substituted derivatives thereof. Other suitable dienes include
bicyclo-(2,2,1)-hepta-2,5-diene (norbornadiene), the dimer of
norbornadiene, and diolefins having two strained ring double bonds, such
as the reaction product obtained by reacting 2,5-norbornadiene with
cyclopentadienyl-1,4,4a,5,8,8a-hexahydro-1,4,5,8-dimethano-naphthalene.
Compounds similar but resulting from the addition of more bridged ring
units by further condensation with cyclopentadiene can also be used.

[0044] In a further aspect, when used in reference to an ethylene
homopolymer (that is, a high density ethylene homopolymer not containing
any comonomer and thus no short chain branches), the terms "homogeneous
ethylene polymer" or "homogeneous linear ethylene polymer" may be used to
describe such a polymer.

[0045] In one aspect, the term "substantially linear ethylene polymer" as
used refers to homogeneously branched ethylene polymers that have long
chain branching. The term does not refer to heterogeneously or
homogeneously branched ethylene polymers that have a linear polymer
backbone. For substantially linear ethylene polymers, the long chain
branches have about the same comonomer distribution as the polymer
backbone, and the long chain branches can be as long as about the same
length as the length of the polymer backbone to which they are attached.
The polymer backbone of substantially linear ethylene polymers is
substituted with about 0.01 long chain branches/1000 carbons to about 3
long chain branches/1000 carbons, more preferably from about 0.01 long
chain branches/1000 carbons to about 1 long chain branches/1000 carbons,
and especially from about 0.05 long chain branches/1000 carbons to about
1 long chain branches/1000 carbons.

[0046] Homogeneously branched ethylene polymers are homogeneous ethylene
polymers that possess short chain branches and that are characterized by
a relatively high composition distribution breadth index (CDBI). That is,
the ethylene polymer has a CDBI greater than or equal to 50 percent,
preferably greater than or equal to 70 percent, more preferably greater
than or equal to 90 percent and essentially lack a measurable high
density (crystalline) polymer fraction.

[0047] The CDBI is defined as the weight percent of the polymer molecules
having a co-monomer content within 50 percent of the median total molar
co-monomer content and represents a comparison of the co-monomer
distribution in the polymer to the co-monomer distribution expected for a
Bernoullian distribution. The CDBI of polyolefins can be conveniently
calculated from data obtained from techniques known in the art, such as,
for example, temperature rising elution fractionation ("TREF") as
described, for example, by Wild, et al., Journal of Polymer Science,
Poly. Phys, Ed., Vol. 20, 441 (1982); L. D. Cady, "The Role of Comonomer
Type and Distribution in LLDPE Product Performance," SPE Regional
Technical Conference, Quaker Square Hilton, Akron, Ohio. 107-119 (Oct.
1-2, 1985); or in U.S. Pat. No. 4,798,081 (Hazlitt, et al.) and U.S. Pat.
No. 5,008,204 (Stehling). However, the TREE technique does not include
purge quantities in CDBI calculations. More preferably, the co-monomer
distribution of the polymer is determined using 13C NMR analysis in
accordance with techniques described, for example, in U.S. Pat. No.
5,292,845 (Kawasaki, et al.) and by J. C. Randall in Rev. Macromol. Chem.
Phys., C29, 201-317.

[0048] The terms "homogeneously branched linear ethylene polymer" and
"homogeneously branched linear ethylene/α-olefin polymer" means
that the olefin polymer has a homogeneous or narrow short branching
distribution (that is, the polymer has a relatively high CDBI) but does
not have long chain branching. That is, the linear ethylene-based polymer
is a homogeneous ethylene polymer characterized by an absence of long
chain branching. Such polymers can be made using polymerization processes
(for example, as described by Elston) which provide a uniform short chain
branching distribution (homogeneously branched). In the polymerization
process described by Elston, soluble vanadium catalyst systems are used
to make such polymers; however, others, such as Mitsui Petrochemical
Industries and Exxon Chemical Company, have reportedly used so-called
single site catalyst systems to make polymers having a homogeneous
structure similar to polymer described by Elston, Further, Ewen, et al.,
and U.S. Pat. No. 5,218,071 (Tsutsui, et al.) disclose the use of
metallocene catalysts for the preparation of homogeneously branched
linear ethylene polymers. Homogeneously branched linear ethylene polymers
are typically characterized as having a molecular weight distribution,
Mw/Mn, of less than 3, preferably less than 2.8, more
preferably less than 2.3.

[0049] In discussing linear ethylene-based polymers, the terms
"homogeneously branched linear ethylene polymer" or "homogeneously
branched linear ethylene/α-olefin polymer" do not refer to high
pressure branched polyethylene which is known to those skilled in the art
to have numerous long chain branches. In one aspect, the term
"homogeneous linear ethylene polymer" generically refers to both linear
ethylene homopolymers and to linear ethylene/α-olefin
interpolymers. For example, a linear ethylene/α-olefin interpolymer
possess short chain branching and the α-olefin is typically at
least one C3-C20, α-olefin (for example, propylene,
1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, and 1-octene).

[0050] The presence of long chain branching can be determined in ethylene
homopolymers by using 13C nuclear magnetic resonance (NMR)
spectroscopy and is quantified using the method described by Randall
(Rev. Macromol. Chem. Phys., C29, V. 2&3, 285-297). There are other known
techniques useful for determining the presence of long chain branches in
ethylene polymers, including ethylene/1-octene interpolymers. Two such
exemplary methods are gel permeation chromatography coupled with a low
angle laser light scattering detector (GPC-LALLS) and gel permeation
chromatography coupled with a differential viscometer detector (GPC-DV).
The use of these techniques for long chain branch detection and the
underlying theories have been well documented in the literature, See, for
example, Zimm, G. H. and Stockmayer, W. H., J. Chem. Phys., 17, 1301
(1949), and Rudin, A., Modern Methods of Polymer Characterization, John
Wiley & Sons, New York (1991) 103-112.

[0051] In a further aspect, substantially linear ethylene polymers are
homogeneously branched ethylene polymers and are disclosed in both U.S.
Pat. Nos. 5,272,236 and 5,278,272 (both Lai, et al.), Homogeneously
branched substantially linear ethylene polymers are available from The
Dow Chemical Company of Midland, Mich. as AFFINITY® polyolefin
plastomers and ENGAGE® polyolefin elastomers, Homogeneously branched
substantially linear ethylene polymers can be prepared via the solution,
slurry, or gas phase polymerization of ethylene and one or more optional
α-olefin comonomers in the presence of a constrained geometry
catalyst, such as the method disclosed in European Patent 0416815
(Stevens, et al.).

[0052] The terms "heterogeneous" and "heterogeneously branched" mean that
the ethylene polymer can be characterized as a mixture of interpolymer
molecules having various ethylene to comonomer molar ratios.
Heterogeneously branched linear ethylene polymers are available from The
Dow Chemical Company as DOWLEX® linear low density polyethylene and as
ATTANE® ultra-low density polyethylene resins. Heterogeneously
branched linear ethylene polymers can be prepared via the solution,
slurry or gas phase polymerization of ethylene and one or more optional
α-olefin comonomers in the presence of a Ziegler Natta catalyst, by
processes such as are disclosed in U.S. Pat. No. 4,076,698 (Anderson, et
al.). Heterogeneously branched ethylene polymers are typically
characterized as having molecular weight distributions, Mw/Mn, from about
3.5 to about 4.1 and, as such, are distinct from substantially linear
ethylene polymers and homogeneously branched linear ethylene polymers in
regards to both compositional short chain branching distribution and
molecular weight distribution.

[0053] The Brookfield viscosity of the ethylene-based polymers is from
about 20 to about 55,000,000 cP as measured at 177° C. using the
Brookfield Viscosity method as described in the Test Methods section.

[0054] Overall, the high crystallinity, ethylene-based polymers have a
density of greater than or equal to about 0.89 g/cm3, preferably greater
than or equal to about 0.91 g/cm3, and preferably less than or equal to
about 0.97 g/cm3. Preferably, these polymers have a density from about
0.89 to about 0.97 g/cm3. All densities are determined by the Density
method as described in the Test Methods section.

[0055] Highly Long Chain Branched Ethylene-Based Polymers

[0056] Highly long chain branched ethylene-based polymers, such as low
density polyethylene (LDPE), can be made using a high-pressure process
using free-radical chemistry to polymerize ethylene monomer. Typical
polymer density is from about 0.91 to about 0.94 g/cm3. The low
density polyethylene may have a melt index (I2) from about 0.01 to
about 150 g/10 minutes. Highly long chain branched ethylene-based
polymers such as LDPE may also be referred to as "high pressure ethylene
polymers", meaning that the polymer is partly or entirely homopolymerized
or copolymerized in autoclave or tubular reactors at pressures above
13,000 psig with the use of free-radical initiators, such as peroxides
(see, for example, U.S. Pat. No. 4,599,392 (McKinney, et al.)). The
process creates a polymer with significant branches, including long chain
branches.

[0057] Highly long chain branched ethylene-based polymers are typically
homopolymers of ethylene; however, the polymer may comprise units derived
from one or more α-olefin copolymers as long as there is at least
50 mole percent polymerized ethylene monomer in the polymer.

[0058] Comonomers that may be used in forming highly branched
ethylene-based polymer include, but are not limited to, α-olefin
comonomers, typically having no more than 20 carbon atoms. For example,
the α-olefin comonomers, for example, may have 3 to 10 carbon
atoms; or in the alternative, the α-olefin comonomers, for example,
may have 3 to 8 carbon atoms. Exemplary α-olefin comonomers
include, but are not limited to, propylene, 1-butene, 1-pentene,
1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and
4-methyl-1-pentene. In the alternative, exemplary comonomers include, but
are not limited to α, β-unsaturated C3-C8-carboxylic
acids, in particular maleic acid, fumaric acid, itaconic acid, acrylic
acid, methacrylic acid and crotonic acid derivates of the α,
β-unsaturated C3-C8-carboxylic acids, for example
unsaturated C3-C15-carboxylic acid esters, in particular ester
of C1-C6-alkanols, or anhydrides, in particular methyl
methacrylate, ethyl methacrylate, n-butyl methacrylate, ter-butyl
methacrylate, methyl acrylate, ethyl acrylate n-butyl acrylate,
2-ethylhexyl acrylate, tert-butyl acrylate, methacrylic anhydride, maleic
anhydride, and itaconic anhydride. In another alternative, the exemplary
comonomers include, but are not limited to, vinyl carboxylates, for
example vinyl acetate. In another alternative, exemplary comonomers
include, but are not limited to, n-butyl acrylate, acrylic acid and
methacrylic acid.

[0059] Process

[0060] The ethylene-based polymer may be produced before or separately
from the reaction process with the highly branched ethylene-based
polymer. In other disclosed processes, the ethylene-based polymer may be
formed in situ and in the presence of highly branched ethylene-based
polymer within a well-stirred reactor such as a tubular reactor or an
autoclave reactor. The highly long chain branched ethylene-based polymer
is formed in the presence of ethylene.

[0061] The ethylenic polymer is formed in the presence of ethylene. FIG. 1
give a general representation of free-radical ethylene polymerization to
form a long chain branch from a radicalized linear ethylene-based polymer
site of forming embodiment ethylenic polymers. Other embodiment processes
for formation of the ethylene-based polymer, the substituent highly
branched ethylene-based polymer, and their combination into the disclosed
ethylenic polymer may exist.

[0062] In a first step of an embodiment process, an ethylene-based polymer
100, as shown in FIG. 1A, is formed. Ethylene-based polymer 100 may be
formed by several different polymer processes, including, but not limited
to, a gas-phase polymerization process, a slurry polymerization process,
and a solution-based polymerization process. In some embodiments, the
ethylene-based polymer 100 is formed in a separate process. Examples of
polymers that may take the form of a ethylene-based polymer 100 include
HDPE, LLDPE, ULDPE, and VLDPE.

[0063] In a second step of an embodiment process, the ethylene-based
polymer 100 further comprises an extractable hydrogen 101 as shown in
FIG. 1B. The ethylene-based polymer 100 enters an area, such as a
reactor, in which free-radical polymerization of ethylene monomer 200
into a highly long chain branched ethylene-based polymer 300 is
supported.

[0064] At some point during this step, a free-radical bearing molecule,
such as a peroxide initiator breakdown product or a growing, highly long
chain branched ethylene-based polymer chain 301, interacts with the
ethylene-based polymer 100 by extracting the extractable hydrogen 101 and
transfers the free radical to the ethylene-based polymer 100. Methods for
extracting the extractable hydrogen 101 from the ethylene-based polymer
100 include, but are not limited to, reaction with free radicals which
are generated by homolytically cleaving molecules (for instance,
peroxide-containing compounds or azo-containing compounds) or by external
radiation.

[0065] In a third step of an embodiment process, the ethylene-based
polymer 100 further comprises a radicalized site 102 after hydrogen
extraction, as shown in FIG. 1c. At this point in the process, and in the
presence of ethylene, either a growing, highly long chain branched
ethylene-based polymer chain 301 or ethylene monomer 200 interacts with
the radicalized site 102 to attach to (via termination) or form a long
chain branch (through polymerization). The reactions between FIGS. 1B and
1C may occur several times with the same ethylene-based polymer.

[0066]FIG. 1D shows a representation of an embodiment ethylenic polymer
400. Linear portion 401 of the embodiment ethylenic polymer 400 is the
portion of the resultant polymer that does not contain a number of long
chain branches 403. The branched portion 402 of the disclosed ethylenic
polymer 400 is the portion of the resultant polymer that does contain a
number of long chain branches 403.

[0067] In an embodiment process, the ethylene-based polymer is prepared
externally to the reaction process used to form the embodiment ethylenic
polymer, combined in a common reactor in the presence of ethylene under
free-radical polymerization conditions, and subjected to process
conditions and reactants to effect the formation of the embodiment
ethylenic polymer.

[0068] In another embodiment process, the highly long chain branched
ethylene-based polymer and the ethylene-based polymer are both prepared
in different forward parts of the same process and are then combined
together in a common downstream part of the process in the presence of
ethylene under free-radical polymerization conditions. The ethylene-based
polymer and the substituent highly long chain branched ethylene-based
polymer are made in separate forward reaction areas or zones, such as
separate autoclaves or an upstream part of a tubular reactor. The
products from these forward reaction areas or zones are then transported
to and combined in a downstream reaction area or zone in the presence of
ethylene under free-radical polymerization conditions to facilitate the
formation of an embodiment ethylenic polymer. In some processes,
additional fresh ethylene is added to the process downstream of the
forward reaction areas or zones to facilitate both the formation of and
grafting of highly long chain branched ethylene-based polymers to the
ethylene-based polymer and the reaction of ethylene monomer directly with
the ethylene-based polymer to form the disclosed ethylenic polymer. In
some other processes, at least one of the product streams from the
forward reaction areas or zones is treated before reaching the downstream
reaction area or zone to neutralize any residue or byproducts that may
inhibit the downstream reactions.

[0069] In an embodiment in situ process, the ethylene-based polymer is
created in a first or forward reaction area or zone, such as a first
autoclave or an upstream part of a tubular reactor. The resultant product
stream is then transported to a downstream reaction area or zone where
there is a presence of ethylene at free-radical polymerization
conditions. These conditions support both the formation of and grafting
of highly long chain branched ethylene-based polymer to the
ethylene-based polymer, thereby forming an embodiment ethylenic polymer.
In some embodiment processes, free radical generating compounds are added
to the downstream reaction area or zone to facilitate the grafting
reaction. In some other embodiment processes, additional fresh ethylene
is added to the process downstream of the forward reaction areas or zones
to facilitate both the formation and grafting of highly long chain
branched ethylene-based polymer to and the reaction of ethylene monomer
with the ethylene-based polymer to form the disclosed ethylenic polymer.
In some embodiment processes, the product stream from the forward
reaction area or zone is treated before reaching the downstream reaction
area or zone to neutralize any residue or byproducts from the previous
reaction that may inhibit the highly branched ethylene-based polymer
formation, the grafting of highly long chain branched ethylene-based
polymer to the ethylene-based polymer, or the reaction of ethylene
monomer with the ethylene-based polymer to form the disclosed ethylenic
polymer.

[0070] For producing the ethylene-based polymer, a gas-phase
polymerization process may be used. The gas-phase polymerization reaction
typically occurs at low pressures with gaseous ethylene, hydrogen, a
catalyst system, for example a titanium containing catalyst, and,
optionally, one or more comonomers, continuously fed to a fluidized-bed
reactor. Such a system typically operates at a pressure from about 300 to
about 350 psi and a temperature from about 80 to about 100° C.

[0071] For producing the ethylene-based polymer, a solution-phase
polymerization process may be used. Typically such a process occurs in a
well-stirred reactor such as a loop reactor or a sphere reactor at
temperature from about 150 to about 575° C., preferably from about
175 to about 205° C., and at pressures from about 30 to about 1000
psi, preferably from about 30 to about 750 psi. The residence time in
such a process is from about 2 to about 20 minutes, preferably from about
10 to about 20 minutes. Ethylene, solvent, catalyst, and optionally one
or more comonomers are fed continuously to the reactor. Exemplary
catalysts in these embodiments include, but are not limited to,
Ziegler-Natta, constrained geometry, and metallocene catalysts. Exemplary
solvents include, but are not limited to, isoparaffins. For example, such
solvents are commercially available under the name ISOPAR E (ExxonMobil
Chemical Co., Houston, Tex.). The resultant mixture of ethylene-based
polymer and solvent is then removed from the reactor and the polymer is
isolated. Solvent is typically recovered via a solvent recovery unit,
that is, heat exchangers and vapor liquid separator drum, and is recycled
back into the polymerization system.

[0072] Any suitable method may be used for feeding the ethylene-based
polymer into a reactor where it may be reacted with a highly long chain
branched ethylene-based polymer. For example, in the cases where the
ethylene-based polymer is produced using a gas phase process, the
ethylene-based polymer may be dissolved in ethylene at a pressure above
the highly long chain branched ethylene-based polymer reactor pressure,
at a temperature at least high enough to dissolve the ethylene-based
polymer and at concentration which does not lead to excessive viscosity
before feeding to the highly long chain branched ethylene-based polymer
reactor.

[0073] For producing the highly long chain branched ethylene-based
polymer, a high pressure, free-radical initiated polymerization process
is typically used. Two different high pressure free-radical initiated
polymerization process types are known. In the first type, an agitated
autoclave vessel having one or more reaction zones is used. The autoclave
reactor normally has several injection points for initiator or monomer
feeds, or both. In the second type, a jacketed tube is used as a reactor,
which has one or more reaction zones. Suitable, but not limiting, reactor
lengths may be from about 100 to about 3000 meters, preferably from about
1000 to about 2000 meters. The beginning of a reaction zone for either
type of reactor is defined by the side injection of either initiator of
the reaction, ethylene, telomer, comonomer(s) as well as any combination
thereof. A high pressure process can be carried out in autoclave or
tubular reactors or in a combination of autoclave and tubular reactors,
each comprising one or more reaction zones.

[0074] In embodiment processes, the catalyst or initiator is injected
prior to the reaction zone where free radical polymerization is to be
induced. In other embodiment processes, the ethylene-based polymer may be
fed into the reaction system at the front of the reactor system and not
formed within the system itself. Termination of catalyst activity may be
achieved by a combination of high reactor temperatures for the free
radical polymerization portion of the reaction or by feeding initiator
into the reactor dissolved in a mixture of a polar solvent such as
isopropanol, water, or conventional initiator solvents such as branched
or unbranched alkanes.

[0075] Embodiment processes may include a process recycle loop to improve
conversion efficiency. In some embodiment processes, the recycle loop may
be treated to neutralize residues or byproducts from the previous
reaction cycle that may inhibit polymerization of either the
ethylene-based polymer or the highly long chain branched ethylene-based
polymer or inhibit the reaction forming the disclosed ethylenic polymer.
In some embodiment processes, fresh monomer is added to this stream.

[0076] Ethylene used for the production of ethylene-based polymers or
highly long chain branched ethylene-based polymer may be purified
ethylene, which is obtained by removing polar components from a loop
recycle stream or by using a reaction system configuration such that only
fresh ethylene is used for making the ethylene-based polymers. It is not
typical that purified ethylene is required to make highly long chain
branched ethylene-based polymer. In such cases ethylene from the recycle
loop may be used.

[0077] Embodiment processes may be used for either the homopolymerization
of ethylene in the presence of an ethylene-based polymer or
copolymerization of ethylene with one or more other comonomers in the
presence of an ethylene-based polymer, provided that these monomers are
copolymerizable with ethylene under free-radical conditions in high
pressure conditions to form highly long chain branched ethylene-based
polymers.

[0078] Chain transfer agents or telogens (CTA) are typically used to
control the melt index in a free-radical polymerization process. Chain
transfer involves the termination of growing polymer chains, thus
limiting the ultimate molecular weight of the polymer material. Chain
transfer agents are typically hydrogen atom donors that will react with a
growing polymer chain and stop the polymerization reaction of the chain.
For high pressure free radical polymerization, these agents can be of
many different types, such as saturated hydrocarbons, unsaturated
hydrocarbons, aldehydes, ketones or alcohols. Typical CTAs that can be
used include, but are not limited to, propylene, isobutane, n-butane,
1-butene, methyl ethyl ketone, propionaldehyde, ISOPAR (ExxonMobil
Chemical Co.), and isopropanol. The amount of CTAs to use in the process
is about 0.03 to about 10 weight percent of the total reaction mixture.

[0079] The melt index (MI or I2) of a polymer, which is inversely
related to the molecular weight, is controlled by manipulating the
concentration of the chain transfer agent. For free radical
polymerization, after the donation of a hydrogen atom, the CTA forms a
radical which can react with the monomers, or with an already formed
oligomers or polymers, to start a new polymer chain. This means that any
functional groups present in the chain transfer agents will be introduced
in the polymer chains. A large number of CTAs, for example, propylene and
1-butene which have an olefinically unsaturated bond, may also be
incorporated in the polymer chain themselves, via a copolymerization
reaction. Polymers produced in the presence of chain transfer agents are
modified in a number of physical properties such as processability,
optical properties such as haze and clarity, density, stiffness, yield
point, film draw and tear strength.

[0080] Hydrogen has been shown to be a chain transfer agent for high
pressure free radical polymerization and in the production of the high
crystallinity ethylene-based polymer. Control of the molecular weight
made in the reaction zones for disclosed processes may be accomplished by
feeding hydrogen to the reaction zones where catalyst or initiator is
injected. The final product melt index control would be accomplished by
feeding chain transfer agents to the reaction zones where free radical
polymerization takes place. Feed of the free radical chain transfer
agents could be accomplished by direct injection into the reaction zones
or by feeding them to the front of the reactor. In some embodiment
processes, it may be necessary to remove excess CTA from the recycle
stream or limit injection so as to prevent excess buildup of CTA in the
front end of the process.

[0081] Free radical initiators that are generally used to produce
ethylene-based polymers are oxygen, which is usable in tubular reactors
in conventional amounts of between 0.0001 and 0.005 wt. % drawn to the
weight of polymerizable monomer, and peroxides. Preferred initiators are
t-butyl peroxy pivalate, di-t-butyl peroxide, t-butyl peroxy acetate and
t-butyl peroxy-2-hexanoate or mixtures thereof. These organic peroxy
initiators are used in conventional amounts of between 0.005 and 0.2 wt.
% drawn to the weight of polymerizable monomers.

[0084] The free radical initiator system further includes at least one
hydrocarbon solvent. The hydrocarbon solvent may, for example, be a
C5 to C30 hydrocarbon solvent. Exemplary hydrocarbon solvents
include, but are not limited to, mineral solvents, normal paraffinic
solvents, isoparaffinic solvents, cyclic solvents, and the like. The
hydrocarbon solvents may, for example, be selected from the group
consisting of n-octane, iso-octane (2,2,4-trimethylpentane), n-dodecane,
iso-dodecane (2,2,4,6,6-pentamethylheptane), and other isoparaffinic
solvents. Exemplary hydrocarbon solvents such as isoparaffinic solvents,
for example, are commercially available under the tradenames ISOPAR C,
ISOPAR E, and ISOPAR H (ExxonMobil Chemical Co.). The hydrocarbon solvent
may comprise less than 99 percent by weight of the free radical initiator
system.

[0085] In some embodiment processes, the free radical initiator system may
further include a polar co-solvent. The polar co-solvent may be an
alcohol co-solvent, for example, a C1 to C30 alcohol.
Additionally, the alcohol functionality of the alcohol co-solvent may,
for example, be mono-functional or multi-functional. Exemplary alcohols
as a polar co-solvent include, but are not limited to, isopropanol
(2-propanol), allylalcohol (1-pentanol), methanol, ethanol, propanol,
butanol, 1,4-butanediol, combinations thereof, mixtures thereof, and the
like. The polar co-solvent may comprise less than 40 percent by weight of
the free radical initiator system.

[0086] The polar co-solvent may be an aldehyde. Aldehydes are generally
known to a person of skill in the art; for example, propionaldehyde may
be used as a polar co-solvent. However, the reactivity potential of
aldehydes as chain transfer agents should be taken into account when
using such aldehydes as polar co-solvents. Such reactivity potentials are
generally known to a person of skill in the art.

[0087] The polar co-solvent may be a ketone. Ketones are generally known
to a person of skill in the art; for example, acetone or tetrahydrofuran
may be used as polar co-solvents. However, the reactivity potential of
ketones as chain transfer agents should be taken into account when using
such ketones as polar co-solvents. Such reactivity potentials are
generally known to a person of skill in the art.

[0088] In some embodiment processes, the free radical initiator system may
further comprise a chain transfer agent as a solvent or as a blend for
simultaneous injection. As previously discussed, chain transfer agents
are generally known to a person of skill in the art, and they include,
but are not limited to, propane, isobutane, acetone, propylene,
isopropanol, butene-1, propionaldehyde, and methyl ethyl ketone. In other
disclosed processes, chain transfer agent may be charged into the reactor
via a separate inlet port from the initiator system. In another
embodiment process, a chain transfer agent may be blended with ethylene,
pressurized, and then injected into the reactor in its own injection
system.

[0089] In some embodiment processes, a peroxide initiator may initially be
dissolved or diluted in a hydrocarbon solvent, and then a polar
co-solvent added to the peroxide initiator/hydrocarbon solvent mixture
prior to metering the free radical initiator system into the
polymerization reactor. In another embodiment process, a peroxide
initiator may be dissolved in the hydrocarbon solvent in the presence of
a polar co-solvent.

[0090] The free-radical initiator used in the process may initiate the
graft site on the linear ethylene-based polymer by extracting the
extractable hydrogen from the linear ethylene-based polymer. Example
free-radical initiators include those free radical initiators previously
discussed, such as peroxides and azo compounds. In some other embodiment
processes, ionizing radiation may also be used to free the extractable
hydrogen and create the radicalized site on the linear ethylene-based
polymer. Organic initiators are preferred means of extracting the
extractable hydrogen, such as using dicumyl peroxide, di-tert-butyl
peroxide, t-butyl perbenzoate, benzoyl peroxide, cumene hydroperoxide,
t-butyl peroctoate, methyl ethyl ketone peroxide,
2,5-dimethyl-2,5-di(tert-butyl peroxy)hexane, lauryl peroxide, and
tert-butyl peracetate, t-butyl α-cumyl peroxide, di-t-butyl
peroxide, di-t-amyl peroxide, t-amyl peroxybenzoate,
1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, α,α'-bis
(t-butylperoxy)-1,3-diisopropylbenzene,
α,α'-bis(t-butylperoxy)-1,4-diisopropylbenzene,
2,5-bis(t-butylperoxy)-2,5-dimethylhexane, and
2,5-bis(t-butylperoxy)-2,5-dimethyl-3-hexyne. A preferred azo compound is
azobisisobutyl nitrite.

[0091] Suitable catalysts for use in embodiment processes include any
compound or combination of compounds that is adapted for preparing
polymers of the desired composition or type, either the ethylene-based
polymers or the highly long chain branched ethylene-based polymers. Both
heterogeneous and homogeneous catalysts, and combinations thereof, may be
employed. In some embodiment processes, heterogeneous catalysts,
including the well known Ziegler-Natta compositions, especially Group 4
metal halides supported on Group 2 metal halides or mixed halides and
alkoxides and the well known chromium or vanadium based catalysts, may be
used. In some embodiment processes, the catalysts for use may be
homogeneous catalysts comprising a relatively pure organometallic
compound or metal complex, especially compounds or complexes based on
metals selected from Groups 3-10 or the Lanthanide series. If more than
one catalyst is used in a system, it is preferred that any catalyst
employed not significantly detrimentally affect the performance of
another catalyst under the conditions of polymerization. Desirably, no
catalyst is reduced in activity by greater than 25 percent, more
preferably greater than 10 percent under the conditions of the
polymerization. Examples of preferred catalyst systems may be found in
U.S. Pat. Nos. 5,272,236 (Lai, et al.); 5,278,272 (Lai, et al.);
6,054,544 (Finlayson, et al.); 6,335,410 (Finlayson, et al.); and
6,723,810 (Finlayson, et al.); PCT Publication Nos. WO 2003/091262
(Boussie, et al.); 2007/136497 (Konze, et al.); 2007/136506 (Konze, et
al.); 2007/136495 (Konze, et al.); and 2007/136496 (Aboelella, et al.).
Other suitable catalysts may be found in U.S. Patent Publication No.
2007/0167578 (Arriola; et al.).

[0092] In some embodiment processes, a coordination-catalysis
polymerization process may be used for the formation of the higher
crystallinity linear ethylene-based polymer. In such embodiment
processes, such catalyst systems would have a suitable tolerance to polar
impurities that would result from impurities in the ethylene feed and
degradation products from free-radical initiators. Control of the amount
of polar impurities fed to the front portion of the reactor for the
target catalyst efficiency could be accomplished by controlling the
amount of polar solvent used in the initiator mixture and by the amount
of material condensed in the process recycle streams. A type of
coordination catalyst may include constrained geometry catalysts (CGC) as
described in U.S. Pat. Nos. 5,272,236 and 5,278,272. Preferred catalysts
in such a CGC system may include the general family of zirconium
catalysts with biphenyl-phenol ligands, including
bis((2-oxoyl-3-(1,1-dimethylethyl)phen-1-yl)-5-(methyl)phenyl)-2-phenoxy)-
propane-1,2-diylzirconium (IV) dimethyl and
bis((2-oxoyl-3-(dibenzo-1H-pyrrole-1-yl)-5-(methyl)phenyl)-2-phenoxy)-tra-
ns-cyclohexane-1,2-dimethylenyl-1,2-diylzirconium (IV) dimethyl, because
they are known to have a good tolerance to polar impurities. Free radical
initiators that generate carbon radicals reduce the amount of polar
impurities in the system and potentially make the use of more
conventional catalysts possible. Examples of carbon-centered free radical
generators include azo compounds, including but not limited to,
azo-bis-is-butyro-nitrile. Such compounds may have a half-life
decomposition temperature of about 30 to about 250° C.
Carbon-carbon initiators, examples of such include dimethyl diphenyl
butane, dimethyl diphenyl hexane, and derivatives thereof, may be used to
reach suitable half-life times under proscribed operating conditions.

[0093] In embodiment processes employing a complex metal catalyst, such a
catalyst may be activated to form an active catalyst composition by
combination with a cocatalyst, preferably a cation forming cocatalyst, a
strong Lewis acid, or a combination thereof. Suitable cocatalysts for use
include polymeric or oligomeric aluminoxanes, especially methyl
aluminoxane, as well as inert, compatible, noncoordinating, ion forming
compounds. So-called modified methyl aluminoxane (MMAO) is also suitable
for use as a cocatalyst. One technique for preparing such modified
aluminoxane is disclosed in U.S. Pat. No. 5,041,584 (Crapo, et al.).
Aluminoxanes can also be made as disclosed in U.S. Pat. Nos. 5,542,199
(Lai, et al.); 4,544,762 (Kaminsky, et al.); 5,015,749 (Schmidt, et al.);
and 5,041,585 (Deavenport, et al.). Other preferred cocatalysts are
inert, noncoordinating, boron compounds, such as perfluoroarylborane
(B(C6F5)3) and the class of compounds known as
(bis-hydrogenated tallowalkyl)methylammonium
tetrakis(pentafluorophenyl)borates, which are mixtures of complexes with
the general chemical structure
([R2NCH3]+[B(C6F5)4]--, wherein R may be a
C14, C16 or C18 alkyl. Other preferred cocatalysts may be
found in U.S. Patent Publication No. 2007/0167578.

[0094] In some embodiment processes, processing aids, such as
plasticizers, can also be included in the embodiment ethylenic polymer
product. These aids include, but are not limited to, the phthalates, such
as dioctyl phthalate and diisobutyl phthalate, natural oils such as
lanolin, and paraffin, naphthenic and aromatic oils obtained from
petroleum refining, and liquid resins from rosin or petroleum feedstocks.
Exemplary classes of oils useful as processing aids include white mineral
oil such as KAYDOL oil (Chemtura Corp.; Middlebury, Conn.) and SHELLFLEX
371 naphthenic oil (Shell Lubricants; Houston, Tex.). Another suitable
oil is TUFFLO oil (Lyondell Lubricants; Houston, Tex.).

[0095] In some embodiment processes, embodiment ethylenic polymers are
treated with one or more stabilizers, for example, antioxidants, such as
IRGANOX 1010 and IRGAFOS 168 (Ciba Specialty Chemicals; Glattbrugg,
Switzerland). In general, polymers are treated with one or more
stabilizers before an extrusion or other melt processes. In other
embodiment processes, other polymeric additives include, but are not
limited to, ultraviolet light absorbers, antistatic agents, pigments,
dyes, nucleating agents, fillers, slip agents, fire retardants,
plasticizers, processing aids, lubricants, stabilizers, smoke inhibitors,
viscosity control agents and anti-blocking agents. The embodiment
ethylenic polymer composition may, for example, comprise less than 10
percent by the combined weight of one or more additives, based on the
weight of the embodiment ethylenic polymer.

[0096] The embodiment ethylenic polymer may further be compounded. In some
embodiment ethylenic polymer compositions, one or more antioxidants may
further be compounded into the polymer and the compounded polymer
pelletized. The compounded ethylenic polymer may contain any amount of
one or more antioxidants. For example, the compounded ethylenic polymer
may comprise from about 200 to about 600 parts of one or more phenolic
antioxidants per one million parts of the polymer. In addition, the
compounded ethylenic polymer may comprise from about 800 to about 1200
parts of a phosphite-based antioxidant per one million parts of polymer.
The compounded disclosed ethylenic polymer may further comprise from
about 300 to about 1250 parts of calcium stearate per one million parts
of polymer.

[0097] Uses

[0098] The embodiment ethylenic polymer may be employed in a variety of
conventional thermoplastic fabrication processes to produce useful
articles, including objects comprising at least one film layer, such as a
monolayer film, or at least one layer in a multilayer film prepared by
cast, blown, calendered, or extrusion coating processes; molded articles,
such as blow molded, injection molded, or rotomolded articles;
extrusions; fibers; and woven or non-woven fabrics. Thermoplastic
compositions comprising the embodiment ethylenic polymer include blends
with other natural or synthetic materials, polymers, additives,
reinforcing agents, ignition resistant additives, antioxidants,
stabilizers, colorants, extenders, crosslinkers, blowing agents, and
plasticizers.

[0099] The embodiment ethylenic polymer may be used in producing fibers
for other applications. Fibers that may be prepared from the embodiment
ethylenic polymer or blends thereof include staple fibers, tow,
multicomponent, sheath/core, twisted, and monofilament. Suitable fiber
forming processes include spunbonded and melt blown techniques, as
disclosed in U.S. Pat. Nos. 4,340,563 (Appel, et al.), 4,663,220
(Wisneski, et al.), 4,668,566 (Nohr, et al.), and 4,322,027 (Reba), gel
spun fibers as disclosed in U.S. Pat. No. 4,413,110 (Kavesh, et al.),
woven and nonwoven fabrics, as disclosed in U.S. Pat. No. 3,485,706
(May), or structures made from such fibers, including blends with other
fibers, such as polyester, nylon or cotton, thermoformed articles,
extruded shapes, including profile extrusions and co-extrusions,
calendared articles, and drawn, twisted, or crimped yarns or fibers.

[0100] The embodiment ethylenic polymer may be used in a variety of films,
including but not limited to clarity shrink films, collation shrink
films, cast stretch films, silage films, stretch hooder films, sealants,
and diaper backsheets.

[0101] The embodiment ethylenic polymer is also useful in other direct
end-use applications. The embodiment ethylenic polymer is useful for wire
and cable coating operations, in sheet extrusion for vacuum forming
operations, and forming molded articles, including the use of injection
molding, blow molding process, or rotomolding processes. Compositions
comprising the embodiment ethylenic polymer can also be formed into
fabricated articles using conventional polyolefin processing techniques.

[0103] Further treatment of the embodiment ethylenic polymer may be
performed to apply the embodiment ethylenic polymer for other end uses.
For example, dispersions (both aqueous and non-aqueous) can also be
formed using the present polymers or formulations comprising the same.
Frothed foams comprising the embodiment ethylenic polymer can also be
formed, as disclosed in PCT Publication No. 2005/021622 (Strandeburg, et
al.). The embodiment ethylenic polymer may also be crosslinked by any
known means, such as the use of peroxide, electron beam, silane, azide,
or other cross-linking technique. The embodiment ethylenic polymer can
also be chemically modified, such as by grafting (for example by use of
maleic anhydride (MAH), silanes, or other grafting agent), halogenation,
amination, sulfonation, or other chemical modification.

[0104] Additives and adjuvants may be added to the embodiment ethylenic
polymer post-formation. Suitable additives include fillers, such as
organic or inorganic particles, including clays, talc, titanium dioxide,
zeolites, powdered metals, organic or inorganic fibers, including carbon
fibers, silicon nitride fibers, steel wire or mesh, and nylon or
polyester cording, nano-sized particles, clays, and so forth; tackifiers,
oil extenders, including paraffinic or napthelenic oils; and other
natural and synthetic polymers, including other polymers that are or can
be made according to the embodiment methods.

[0106] Blends and mixtures of the embodiment ethylenic polymer may include
thermoplastic polyolefin blends (TPO), thermoplastic elastomer blends
(TPE), thermoplastic vulcanizates (TPV) and styrenic polymer blends. TPE
and TPV blends may be prepared by combining embodiment ethylenic
polymers, including functionalized or unsaturated derivatives thereof,
with an optional rubber, including conventional block copolymers,
especially an SBS block copolymer, and optionally a crosslinking or
vulcanizing agent. TPO blends are generally prepared by blending the
embodiment polymers with a polyolefin, and optionally a crosslinking or
vulcanizing agent. The foregoing blends may be used in forming a molded
object, and optionally crosslinking the resulting molded article. A
similar procedure using different components has been previously
disclosed in U.S. Pat. No. 6,797,779 (Ajbani, et al.).

[0107] Definitions

[0108] The term "composition," as used, includes a mixture of materials
which comprise the composition, as well as reaction products and
decomposition products formed from the materials of the composition.

[0109] The terms "blend" or "polymer blend," as used, mean an intimate
physical mixture (that is, without reaction) of two or more polymers. A
blend may or may not be miscible (not phase separated at molecular
level). A blend may or may not be phase separated. A blend may or may not
contain one or more domain configurations, as determined from
transmission electron spectroscopy, light scattering, x-ray scattering,
and other methods known in the art. The blend may be effected by
physically mixing the two or more polymers on the macro level (for
example, melt blending resins or compounding) or the micro level (for
example, simultaneous forming within the same reactor).

[0110] The term "linear" refers to polymers where the polymer backbone of
the polymer lacks measurable or demonstrable long chain branches, for
example, the polymer is substituted with an average of less than 0.01
long branch per 1000 carbons.

[0111] The term "polymer" refers to a polymeric compound prepared by
polymerizing monomers, whether of the same or a different type. The
generic term polymer thus embraces the term "homopolymer," usually
employed to refer to polymers prepared from only one type of monomer, and
the term "interpolymer" as defined. The terms "ethylene/α-olefin
polymer" is indicative of interpolymers as described.

[0112] The term "interpolymer" refers to polymers prepared by the
polymerization of at least two different types of monomers. The generic
term interpolymer includes copolymers, usually employed to refer to
polymers prepared from two different monomers, and polymers prepared from
more than two different types of monomers.

[0113] The term "ethylene-based polymer" refers to a polymer that contains
more than 50 mole percent polymerized ethylene monomer (based on the
total amount of polymerizable monomers) and, optionally, may contain at
least one comonomer.

[0114] The term "ethylene/α-olefin interpolymer" refers to an
interpolymer that contains more than 50 mole percent polymerized ethylene
monomer (based on the total amount of polymerizable monomers) and at
least one α-olefin.

[0115] The term "ethylenic polymer" refers to a polymer resulting from the
bonding of an ethylene-based polymer and at least one highly long chain
branched ethylene-based polymer.

Test Methods

[0116] Density

[0117] Samples that are measured for density are prepared according to
ASTM D 1928. Measurements are made within one hour of sample pressing
using ASTM D792, Method B.

[0118] For some highly long chain branched ethylene-based polymers,
density is calculated ("calculated density") in grams per cubic
centimeter based upon a relationship with the heat of fusion (Hf) in
Joules per gram of the sample. The heat of fusion of the polymer sample
is determined using the DSC Crystallinity method described infra.

[0119] To establish a relationship between density and heat of fusion for
highly branched ethylene based polymers, thirty commercially available
LDPE resins (designated "Commercially Available Resins" or "CAR") are
tested for density, melt index (I2), heat of fusion, peak melting
temperature, g', gpcBR, and LCBf using the Density, Melt Index, DSC
Crystallinity, Gel Permeation Chromatography, g' by 3D-GPC, and gpcBR
Branching Index by 3D-GPC methods, all described infra. The Commercially
Available Resins have the properties listed in Table 1.

[0120] A graph showing the relationship between density and heat of fusion
(Hf) for the Commercially Available Resins is shown in FIG. 2.
R2 given in FIG. 2 is the square of a correlation coefficient
between the observed and modeled data values. Based upon a linear
regression, a calculated density, in grams per cubic centimeter, of
commercially available highly long chain branched ethylene based polymers
can be determined from the heat of fusion, in Joules per gram, using
Equation 1:

Calculated density=5.03E-04*(Hf)+8.46E-01 (Eq. 1).

[0121] Melt Index

[0122] Melt index, or I2, is measured in accordance with ASTM D 1238,
Condition 190° C./2.16 kg, and is reported in grams eluted per 10
minutes. I10 is measured in accordance with ASTM D 1238, Condition
190° C./10 kg, and is reported in grams eluted per 10 minutes.

[0123] Brookfield Viscosity

[0124] Melt viscosity is determined using a Brookfield Laboratories
(Middleboro, Mass.) DVII+ Viscometer and disposable aluminum sample
chambers. The spindle used is a SC-31 hot-melt spindle suitable for
measuring viscosities from about 10 to about 100,000 centipoises. Other
spindles may be used to obtain viscosities if the viscosity of the
polymer is out of this range or in order to obtain the recommended torque
ranges as described in this procedure. The sample is poured into the
sample chamber, inserted into a Brookfield Thermosel, and locked into
place. The sample chamber has a notch on the bottom that fits the bottom
of the Brookfield Thermosel to ensure that the chamber is not allowed to
turn when the spindle is inserted and spinning The sample is heated to
the required temperature (177° C.), until the melted sample is
about 1 inch (approximately 8 grams of resin) below the top of the sample
chamber. The viscometer apparatus is lowered and the spindle submerged
into the sample chamber. Lowering is continued until brackets on the
viscometer align on the Thermosel. The viscometer is turned on, and set
to operate at a shear rate which leads to a torque reading from about 30
to about 60 percent. Readings are taken every minute for about 15 minutes
or until the values stabilize, at which point, a final reading is
recorded.

[0125] DSC Crystallinity

[0126] Differential Scanning calorimetry (DSC) can be used to measure the
melting and crystallization behavior of a polymer over a wide range of
temperature. For example, the TA Instruments Q1000 DSC, equipped with an
RCS (refrigerated cooling system) and an autosampler is used to perform
this analysis. During testing, a nitrogen purge gas flow of 50 ml/min is
used. Each sample is melt pressed into a thin film at about 175°
C.; the melted sample is then air-cooled to room temperature
(˜25° C.). A 3-10 mg, 6 mm diameter specimen is extracted
from the cooled polymer, weighed, placed in a light aluminum pan (ca 50
mg), and crimped shut. Analysis is then performed to determine its
thermal properties.

[0127] The thermal behavior of the sample is determined by ramping the
sample temperature up and down to create a heat flow versus temperature
profile. First, the sample is rapidly heated to 180° C. and held
isothermal for 3 minutes in order to remove its thermal history. Next,
the sample is cooled to -40° C. at a 10° C./minute cooling
rate and held isothermal at -40° C. for 3 minutes. The sample is
then heated to 150° C. (this is the "second heat" ramp) at a
10° C./minute heating rate. The cooling and second heating curves
are recorded. The cool curve is analyzed by setting baseline endpoints
from the beginning of crystallization to -20° C. The heat curve is
analyzed by setting baseline endpoints from -20° C. to the end of
melt. The values determined are peak melting temperature (Tm), peak
crystallization temperature (Tc), heat of fusion (Hf) (in
Joules per gram), and the calculated % crystallinity for polyethylene
samples using Equation 2:

%Crystallinity=((Hf)/(292 J/g))×100 (Eq. 2).

[0128] The heat of fusion (Hf) and the peak melting temperature are
reported from the second heat curve. Peak crystallization temperature is
determined from the cooling curve.

[0129] Gel Permeation Chromatography (GPC)

[0130] The GPC system consists of a Waters (Milford, Mass.) 150 C high
temperature chromatograph (other suitable high temperatures GPC
instruments include Polymer Laboratories (Shropshire, UK) Model 210 and
Model 220) equipped with an on-board differential refractometer (RI).
Additional detectors can include an IR4 infra-red detector from Polymer
ChAR (Valencia, Spain), Precision Detectors (Amherst, Mass.) 2-angle
laser light scattering detector Model 2040, and a Viscotek (Houston,
Tex.) 150R 4-capillary solution viscometer. A GPC with the last two
independent detectors and at least one of the first detectors is
sometimes referred to as "3D-GPC", while the term "GPC" alone generally
refers to conventional GPC. Depending on the sample, either the 15-degree
angle or the 90-degree angle of the light scattering detector is used for
calculation purposes. Data collection is performed using Viscotek TriSEC
software, Version 3, and a 4-channel Viscotek Data Manager DM400. The
system is also equipped with an on-line solvent degassing device from
Polymer Laboratories (Shropshire, UK). Suitable high temperature GPC
columns can be used such as four 30 cm long Shodex HT803 13 micron
columns or four 30 cm Polymer Labs columns of 20-micron mixed-pore-size
packing (MixA LS, Polymer Labs). The sample carousel compartment is
operated at 140° C. and the column compartment is operated at
150° C. The samples are prepared at a concentration of 0.1 grams
of polymer in 50 milliliters of solvent. The chromatographic solvent and
the sample preparation solvent contain 200 ppm of butylated
hydroxytoluene (BHT). Both solvents are sparged with nitrogen. The
polyethylene samples are gently stirred at 160° C. for four hours.
The injection volume is 200 microliters. The flow rate through the GPC is
set at 1 ml/minute.

[0131] The GPC column set is calibrated before running the Examples by
running twenty-one narrow molecular weight distribution polystyrene
standards. The molecular weight (MW) of the standards ranges from 580 to
8,400,000 grams per mole, and the standards are contained in 6 "cocktail"
mixtures. Each standard mixture has at least a decade of separation
between individual molecular weights. The standard mixtures are purchased
from Polymer Laboratories (Shropshire, UK). The polystyrene standards are
prepared at 0.025 g in 50 mL of solvent for molecular weights equal to or
greater than 1,000,000 grams per mole and 0.05 g in 50 ml of solvent for
molecular weights less than 1,000,000 grams per mole. The polystyrene
standards were dissolved at 80° C. with gentle agitation for 30
minutes. The narrow standards mixtures are run first and in order of
decreasing highest molecular weight component to minimize degradation.
The polystyrene standard peak molecular weights are converted to
polyethylene Mw using the Mark-Houwink K and a (sometimes referred
to as α) values mentioned later for polystyrene and polyethylene.
See the Examples section for a demonstration of this procedure.

[0132] With 3D-GPC absolute weight average molecular weight ("Mw,
Abs") and intrinsic viscosity are also obtained independently from
suitable narrow polyethylene standards using the same conditions
mentioned previously. These narrow linear polyethylene standards may be
obtained from Polymer Laboratories (Shropshire, UK; Part No.'s
PL2650-0101 and PL2650-0102).

[0133] The systematic approach for the determination of multi-detector
offsets is performed in a manner consistent with that published by Balke,
Mourey, et al. (Mourey and Balke, Chromatography Polym., Chapter 12,
(1992)) (Balke, Thitiratsakul, Lew, Cheung, Mourey, Chromatography
Polym., Chapter 13, (1992)), optimizing triple detector log (Mw and
intrinsic viscosity) results from Dow 1683 broad polystyrene (American
Polymer Standards Corp.; Mentor, Ohio) or its equivalent to the narrow
standard column calibration results from the narrow polystyrene standards
calibration curve. The molecular weight data, accounting for detector
volume off-set determination, are obtained in a manner consistent with
that published by Zimm (Zimm, B. H., J. Chem. Phys., 16, 1099 (1948)) and
Kratochvil (Kratochvil, P., Classical Light Scattering from Polymer
Solutions, Elsevier, Oxford, N.Y. (1987)). The overall injected
concentration used in the determination of the molecular weight is
obtained from the mass detector area and the mass detector constant
derived from a suitable linear polyethylene homopolymer, or one of the
polyethylene standards. The calculated molecular weights are obtained
using a light scattering constant derived from one or more of the
polyethylene standards mentioned and a refractive index concentration
coefficient, dn/dc, of 0.104. Generally, the mass detector response and
the light scattering constant should be determined from a linear standard
with a molecular weight in excess of about 50,000 daltons. The viscometer
calibration can be accomplished using the methods described by the
manufacturer or alternatively by using the published values of suitable
linear standards such as Standard Reference Materials (SRM) 1475a, 1482a,
1483, or 1484a. The chromatographic concentrations are assumed low enough
to eliminate addressing 2nd viral coefficient effects (concentration
effects on molecular weight).

[0134] Analytical Temperature Rising Elution Fractionation (ATREF)

[0135] ATREF analysis is conducted according to the methods described in
U.S. Pat. No. 4,798,081 (Hazlitt, et al.) and Wild, L.; Ryle, T. R.;
Knobeloch, D. C.; Peat, I. R.; "Determination of Branching Distributions
in Polyethylene and Ethylene Copolymers", J. Polym. Sci., 20, 441-55
(1982). The configurations and equipment are described in Hazlitt, L. G.,
"Determination of Short-chain Branching Distributions of Ethylene
Copolymers by Automated Temperature Rising Elution Fractionation
(Auto-ATREF)", Journal of Applied Polymer Science: Appl. Polym. Symp.,
45, 25-39 (1990). The polymer sample is dissolved in TCB (0.2% to 0.5% by
weight) at 120° C. to 140° C., loaded on the column at an
equivalent temperature, and allowed to crystallize in a column containing
an inert support (stainless steel shot, glass beads, or a combination
thereof) by slowly reducing the temperature to 20° C. at a cooling
rate of 0.1° C./minute. The column is connected to an infrared
detector (and, optionally, to a LALLS detector and viscometer)
commercially available as described in the Gel Permeation Chromatography
Method section. An ATREF chromatogram curve is then generated by eluting
the crystallized polymer sample from the column while increasing the
temperature (1° C./minute) of the column and eluting solvent from
20 to 120° C. at a rate of 1.0° C./minute.

[0138] In F-TREF, 120 mg of the sample is added into a Crystex reactor
vessel with 40 ml of ODCB held at 160° C. for 60 minutes with
mechanical stirring to achieve sample dissolution. The sample is loaded
onto TREF column. The sample solution is then cooled down in two stages:
(1) from 160° C. to 100° C. at 40° C./minute, and
(2) the polymer crystallization process started from 100° C. to
30° C. at 0.4° C./minute. Next, the sample solution is held
isothermally at 30° C. for 30 minutes. The temperature-rising
elution process starts from 30° C. to 160° C. at
1.5° C./minute with flow rate of 0.6 ml/minute. The sample loading
volume is 0.8 ml. Sample molecular weight (Mw) is calculated as the
ratio of the 15° or 90° LS signal over the signal from
measuring sensor of IR-4 detector. The LS-MW calibration constant is
obtained by using polyethylene national bureau of standards SRM 1484a.
The elution temperature is reported as the actual oven temperature. The
tubing delay volume between the TREF and detector is accounted for in the
reported TREF elution temperature.

[0141] Samples are prepared by dissolution in trichlorobenzene (TCB)
containing approximately 0.5% 2,6-di-tert-butyl-4-methylphenol at
160° C. with a magnetic stir bar providing agitation. Sample load
is approximately 150 mg per column. After loading at 125° C., the
column and sample are cooled to 25° C. over approximately 72
hours. The cooled sample and column are then transferred to the second
temperature programmable bath and equilibrated at 25° C. with a 4
ml/minute constant flow of TCB. A linear temperature program is initiated
to raise the temperature approximately 0.33° C./minute, achieving
a maximum temperature of 102° C. in approximately 4 hours.

[0142] Fractions are collected manually by placing a collection bottle at
the outlet of the IR detector. Based upon earlier ATREF analysis, the
first fraction is collected from 56 to 60° C. Subsequent small
fractions, called subfractions, are collected every 4° C. up to
92° C., and then every 2° C. up to 102° C.
Subfractions are referred to by the midpoint elution temperature at which
the subfraction is collected.

[0143] Subfractions are often aggregated into larger fractions by ranges
of midpoint temperature to perform testing. For the purposes of testing
embodiment ethylenic polymers, subfractions with midpoint temperatures in
the range of 97 to 101° C. are combined together to give a
fraction called "Fraction A". Subfractions with midpoint temperatures in
the range of 90 to 95° C. are combined together to give a fraction
called "Fraction B". Subfractions with midpoint temperatures in the range
of 82 to 86° C. are combined together to give a fraction called
"Fraction C". Subfractions with midpoint temperatures in the range of 62
to 78° C. are combined together to give a fraction called
"Fraction D". Fractions may be further combined into larger fractions for
testing purposes.

[0144] A weight-average elution temperature is determined for each
Fraction based upon the average of the elution temperature range for each
subfraction and the weight of the subfraction versus the total weight of
the sample. Weight average temperature as determined by Equation 3 is
defined as:

T W = T T ( f ) * A ( f ) / T
A ( f ) , ( Eq . 3 ) ##EQU00001##

where T(f) is the mid-point temperature of a narrow slice or segment and
A(f) is the area of the segment, proportional to the amount of polymer,
in the segment.

[0147] Fractions A, B, C, and D are prepared for subsequent analysis by
removal of trichlorobenzene (TCB). This is a multi-step process in which
one part TCB solution is combined with three parts methanol. The
precipitated polymer for each fraction is filtered onto fluoropolymer
membranes, washed with methanol, and air dried. The polymer-containing
filters are then placed in individual vials with enough xylene to cover
the filter. The vials are heated to 135° C., at which point the
polymer either dissolves in the xylene or is lifted from the filter as
plates or flakes. The vials are cooled, the filters are removed, and the
xylene is evaporated under a flowing nitrogen atmosphere at room
temperature. The vials are then placed in a vacuum oven, the pressure
reduced to -28 inches Hg, and the temperature raised to 80° C. for
two hours to remove residual xylene. The four Fractions are analyzed
using IR spectroscopy and gel permeation chromatography to obtain a
number average molecular weight. For IR analysis, Fractions may have to
be combined into larger fractions to obtain a high enough signal to noise
in the IR spectra.

[0148] Methyls Per 1000 Carbons Determination on P-TREF Fractions

[0149] The analysis follows Method B in ASTM D-2238 except for slight
deviation in the procedure to account for smaller-than-standard sample
sizes, as described in this procedure. In the ASTM procedure polyethylene
films approximately 0.25 mm thick are scanned by infrared and analyzed.
The procedure described is modified to permit similar testing using
smaller amounts of material generated by the P-TREF separation.

[0150] For each of the Fractions, a piece of polymer is pressed between
aluminum foil in a heated hydraulic press to create a film approximately
4 mm in diameter and 0.02 mm thick. The film is then placed on a NaCl
disc 13 mm in diameter and 2 mm thick and scanned by infrared using an IR
microscope. The FTIR spectrometer is a Thermo Nicolet Nexus 470 with a
Continuum microscope equipped with a liquid nitrogen cooled MCT detector.
One hundred twenty eight scans are collected at 2 wavenumber resolution
using 1 level of 0 filling.

[0151] The methyls are measured using the 1378 cm-1 peak. The
calibration used is the same calibration derived by using ASTM D-2238.
The FTIR is equipped with Thermo Nicolet Omnic software.

[0152] The uncorrected methyls per 1000 carbons, X, are corrected for
chain ends using their corresponding number average molecular weight,
Mn, to obtain corrected methyls per thousand, Y, as shown in
Equation 4:

Y=X-21,000/Mn (Eq. 4).

[0153] The value of 21,000 is used to allow for the lack of reliable
signal to obtain unsaturation levels in the sub-fractions. In general,
though, these corrections are small (<0.4 methyls per 1000 carbons).

[0154] g' by 3D-GPC

[0155] The index (g') for the sample polymer is determined by first
calibrating the light scattering, viscosity, and concentration detectors
described in the Gel Permeation Chromatography method supra with SRM
1475a homopolymer polyethylene (or an equivalent reference). The light
scattering and viscometer detector offsets are determined relative to the
concentration detector as described in the calibration. Baselines are
subtracted from the light scattering, viscometer, and concentration
chromatograms and integration windows are then set making certain to
integrate all of the low molecular weight retention volume range in the
light scattering and viscometer chromatograms that indicate the presence
of detectable polymer from the refractive index chromatogram. A linear
homopolymer polyethylene is used to establish a Mark-Houwink (MH) linear
reference line by injecting a broad molecular weight polyethylene
reference such as SRM1475a standard, calculating the data file, and
recording the intrinsic viscosity (IV) and molecular weight (Mw),
each derived from the light scattering and viscosity detectors
respectively and the concentration as determined from the RI detector
mass constant for each chromatographic slice. For the analysis of samples
the procedure for each chromatographic slice is repeated to obtain a
sample Mark-Houwink line. Note that for some samples the lower molecular
weights, the intrinsic viscosity and the molecular weight data may need
to be extrapolated such that the measured molecular weight and intrinsic
viscosity asymptotically approach a linear homopolymer GPC calibration
curve. To this end, many highly-branched ethylene-based polymer samples
require that the linear reference line be shifted slightly to account for
the contribution of short chain branching before proceeding with the long
chain branching index (g') calculation.

[0156] A g-prime (gi') is calculated for each branched sample
chromatographic slice (i) and measuring molecular weight (Mi)
according to Equation 5:

gi'=(IV.sub.sample,i/IVlinear reference,j) (Eq. 5),

where the calculation utilizes the IVlinear reference,j at
equivalent molecular weight, Mj, in the linear reference sample. In
other words, the sample IV slice (i) and reference IV slice (j) have the
same molecular weight (Mi=Mj). For simplicity, the
IVlinear reference,j slices are calculated from a fifth-order
polynomial fit of the reference Mark-Houwink Plot. The IV ratio, or
gi', is only obtained at molecular weights greater than 3,500
because of signal-to-noise limitations in the light scattering data. The
number of branches along the sample polymer (Bn) at each data slice
(i) can be determined by using Equation 6, assuming a viscosity shielding
epsilon factor of 0.75:

[0159] In the 3D-GPC configuration the polyethylene and polystyrene
standards can be used to measure the Mark-Houwink constants, K and
α, independently for each of the two polymer types, polystyrene and
polyethylene. These can be used to refine the Williams and Ward
polyethylene equivalent molecular weights in application of the following
methods.

[0160] The gpcBR branching index is determined by first calibrating the
light scattering, viscosity, and concentration detectors as described
previously. Baselines are then subtracted from the light scattering,
viscometer, and concentration chromatograms. Integration windows are then
set to ensure integration of all of the low molecular weight retention
volume range in the light scattering and viscometer chromatograms that
indicate the presence of detectable polymer from the refractive index
chromatogram. Linear polyethylene standards are then used to establish
polyethylene and polystyrene Mark-Houwink constants as described
previously. Upon obtaining the constants, the two values are used to
construct two linear reference conventional calibrations ("cc") for
polyethylene molecular weight and polyethylene intrinsic viscosity as a
function of elution volume, as shown in Equations 8 and 9:

[0161] The gpcBR branching index is a robust method for the
characterization of long chain branching. See Yau, Wallace W., "Examples
of Using 3D-GPC--TREF for Polyolefin Characterization", Macromol. Symp.,
2007, 257, 29-45. The index avoids the slice-by-slice 3D-GPC calculations
traditionally used in the determination of g' values and branching
frequency calculations in favor of whole polymer detector areas and area
dot products. From 3D-GPC data, one can obtain the sample bulk Mw by
the light scattering (LS) detector using the peak area method. The method
avoids the slice-by-slice ratio of light scattering detector signal over
the concentration detector signal as required in the g' determination.

M W = i w i M i = i ( C i
i C i ) M i = i C i M i i
C i = i LS i i C i = LS
Area Conc . Area . ( Eq . 10 ) ##EQU00005##

[0162] The area calculation in Equation 10 offers more precision because
as an overall sample area it is much less sensitive to variation caused
by detector noise and GPC settings on baseline and integration limits.
More importantly, the peak area calculation is not affected by the
detector volume offsets. Similarly, the high-precision sample intrinsic
viscosity (IV) is obtained by the area method shown in Equation 11:

IV = [ η ] = i w i IV i = i
( C i i C i ) IV i = i C i
IV i i C i = i DP i i C i
= DP Area Conc . Area , ( Eq . 11 )
##EQU00006##

where DPi stands for the differential pressure signal monitored
directly from the online viscometer.

[0163] To determine the gpcBR branching index, the light scattering
elution area for the sample polymer is used to determine the molecular
weight of the sample. The viscosity detector elution area for the sample
polymer is used to determine the intrinsic viscosity (IV or [η]) of
the sample.

[0164] Initially, the molecular weight and intrinsic viscosity for a
linear polyethylene standard sample, such as SRM1475a or an equivalent,
are determined using the conventional calibrations for both molecular
weight and intrinsic viscosity as a function of elution volume, per
Equations 12 and 13:

Mw CC = i ( C i i C i ) M i
= i w i M i , and ( Eq . 12 )
[ η ] CC = i ( C i i C i ) IV
i = i w i IV i . ( Eq . 13 )
##EQU00007##

where [η] is the measured intrinsic viscosity, [η]cc is the
intrinsic viscosity from the conventional calibration, Mw is the
measured weight average molecular weight, and Mw,cc is the weight
average molecular weight of the conventional calibration. The Mw by light
scattering (LS) using Equation (10) is commonly referred to as the
absolute Mw; while the Mw,cc from Equation (12) using the conventional
GPC molecular weight calibration curve is often referred to as polymer
chain Mw. All statistical values with the "cc" subscript are determined
using their respective elution volumes, the corresponding conventional
calibration as previously described, and the concentration (Ci)
derived from the mass detector response. The non-subscripted values are
measured values based on the mass detector, LALLS, and viscometer areas.
The value of KPE is adjusted iteratively until the linear reference
sample has a gpcBR measured value of zero. For example, the final values
for α and Log K for the determination of gpcBR in this particular
case are 0.725 and -3.355, respectively, for polyethylene, and 0.722 and
-3.993 for polystyrene, respectively.

[0165] Once the K and α values have been determined, the procedure
is repeated using the branched samples. The branched samples are analyzed
using the final Mark-Houwink constants as the best "cc" calibration
values and applying Equations 10-14.

[0166] The interpretation of gpcBR is straight forward. For linear
polymers, gpcBR calculated from Equation 14 will be close to zero since
the values measured by LS and viscometry will be close to the
conventional calibration standard. For branched polymers, gpcBR will be
higher than zero, especially with high levels of LCB, because the
measured polymer Mw will be higher than the calculated Mw,cc,
and the calculated IVcc will be higher than the measured polymer IV.
In fact, the gpcBR value represents the fractional IV change due the
molecular size contraction effect as the result of polymer branching. A
gpcBR value of 0.5 or 2.0 would mean a molecular size contraction effect
of IV at the level of 50% and 200%, respectively, versus a linear polymer
molecule of equivalent weight.

[0167] For these particular Examples, the advantage of using gpcBR in
comparison to the g' index and branching frequency calculations is due to
the higher precision of gpcBR. All of the parameters used in the gpcBR
index determination are obtained with good precision and are not
detrimentally affected by the low 3D-GPC detector response at high
molecular weight from the concentration detector. Errors in detector
volume alignment also do not affect the precision of the gpcBR index
determination. In other particular cases, other methods for determining
Mw moments may be preferable to the aforementioned technique.

[0168] Nuclear Magnetic Resonance (13C NMR)

[0169] Samples involving LDPE and the inventive examples are prepared by
adding approximately 3 g of a 50/50 mixture of
tetrachloroethane-d2/orthodichlorobenzene containing 0.025 M
Cr(AcAc)3 to a 0.25 g polymer sample in a 10 mm NMR tube. Oxygen is
removed from the sample by placing the open tubes in a nitrogen
environment for at least 45 minutes. The samples are then dissolved and
homogenized by heating the tube and its contents to 150° C. using
a heating block and heat gun. Each dissolved sample is visually inspected
to ensure homogeneity. Samples are thoroughly mixed immediately prior to
analysis and were not allowed to cool before insertion into the heated
NMR sample holders.

[0170] The ethylene-based polymer samples are prepared by adding
approximately 3 g of a 50/50 mixture of
tetrachloroethane-d2/orthodichlorobenzene containing 0.025 M
Cr(AcAc)3 to 0.4 g polymer sample in a 10 mm NMR tube. Oxygen is
removed from the sample by placing the open tubes in a nitrogen
environment for at least 45 minutes. The samples are then dissolved and
homogenized by heating the tube and its contents to 150° C. using
a heating block and heat gun. Each dissolved sample is visually inspected
to ensure homogeneity. Samples are thoroughly mixed immediately prior to
analysis and are not allowed to cool before insertion into the heated NMR
sample holders.

[0171] All data are collected using a Bruker 400 MHz spectrometer. The
data is acquired using a 6 second pulse repetition delay, 90-degree flip
angles, and inverse gated decoupling with a sample temperature of
125° C. All measurements are made on non-spinning samples in
locked mode. Samples are allowed to thermally equilibrate for 15 minutes
prior to data acquisition. The 13C NMR chemical shifts were
internally referenced to the EEE triad at 30.0 ppm.

[0175] The cross-fractionation by TREF (xTREF) provides a separation by
both molecular weight and crystallinity using ATREF and GPC. Nakano and
Goto, J. Appl. Polym. Sci., 24, 4217-31 (1981), described the first
development of an automatic cross fractionation instrument. The typical
xTREF process involves the slow crystallization of a polymer sample onto
an ATREF column (composed of glass beads and steel shot). After the ATREF
step of crystallization the polymer is sequentially eluted in
predetermined temperature ranges from the ATREF column and the separated
polymer fractions are measured by GPC. The combination of the elution
temperature profile and the individual GPC profiles allow for a
3-dimensional representation of a more complete polymer structure (weight
distribution of polymer as function of molecular weight and
crystallinity). Since the elution temperature is a good indicator for the
presence of short chain branching, the method provides a fairly complete
structural description of the polymer.

[0176] A detailed description of the design and operation of the
cross-fractionation instrument can be found in PCT Publication No. WO
2006/081116 (Gillespie, et al.). FIG. 12 shows a schematic for the xTREF
instrument 500. This instrument has a combination of at least one ATREF
oven 600 and a GPC 700. In this method, a Waters GPC 150 is used. The
xTREF instrument 500, through a series of valve movements, operates by
(1) injecting solutions into a sample loop and then to the ATREF column,
(2) crystallizing the polymer by cooling the ATREF oven/column, and (3)
eluting the fractions in step-wise temperature increments into the GPC.
Heated transfer lines 505, kept at approximately 150° C., are used
for effluent flow between various components of the xTREF instrument 500.
Five independent valve systems (GPC 700 2-way/6-port valve 750 and
2-way/3-port valve 760; ATREF oven 600 valves 650, 660, and 670) control
the flow path of the sample.

[0177] The refractive index (RI) GPC detector 720 is quite sensitive to
solvent flow and temperature. Fluctuations in the solvent pressure during
crystallization and elution can lead to elution artifacts during the TREF
elution. An external infrared (IR) detector 710, the IR4, supplied by
Polymer ChAR (Valencia, Spain) is added as the primary concentration
detector (RI detector 720) to alleviate this concern. Other detectors
(not shown) are the LALLS and viscometer configured as described in the
Gel Permeation Chromatography method, provided infra in the Testing
Methods section. In FIG. 12, a 2-way/6-port valve 750 and a 2-way/3-port
valve 760 (Valco; Houston, Tex.) are placed in the Waters 150 C heated
column compartment 705.

[0178] Each ATREF oven 600 (Gaumer Corporation, Houston, Tex.) uses a
forced flow gas (nitrogen) design and are well insulated. Each ATREF
column 610 is constructed of 316 SS 0.125'' OD by 0.105'' (3.18
millimeter) ID precision bore tubing. The tubing is cut to 19.5'' (495.3
millimeters) length and filled with a 60/40 (v/v) mix of stainless steel
0.028'' (0.7 millimeter) diameter cut wire shot and 30-40 mesh spherical
technical quality glass. The stainless steel cut wire shot is from
Pellets, Inc. (North Tonawanda, N.Y.). The glass spheres are from Potters
Industries (Brownwood, Tex.). The interstitial volume was approximately
1.00 ml. Parker fitted low internal volume column end fittings (Part
number 2-1 Z2HCZ-4-SS) are placed on each tube end and the tubing is
wrapped into a 1.5'' (38.1 millimeters) coil. Since TCB has a very high
heat capacity at a standard flowrate of 1.0 ml/minute, the ATREF column
610 (which has an interstitial volume of around 1 ml) may be heated or
quenched without the pre-equilibration coil 605. It should be noted that
the pre-equilibration coil 605 has a large volume (>12 milliliters)
and, therefore, is only inline during the ATREF elution cycle (and not
the ATREF loading cycle). The nitrogen to the ATREF oven 600 passed
through a thermostatically controlled chiller (Airdyne; Houston, Tex.)
with a 100 psig nitrogen supply capable of discharging 100 scf/minute of
5 to 8° C. nitrogen. The chilled nitrogen is piped to each
analytical oven for improved low temperature control purposes.

[0179] The polyethylene samples are prepared in 2-4 mg/ml TCB depending
upon the distribution, density, and the desired number of fractions to be
collected. The samples preparation is similar to that of conventional
GPC.

[0180] The system flow rate is controlled at 1 ml/minute for both the GPC
elution and the ATREF elution using the GPC pump 740 and GPC sample
injector 745. The GPC separation is accomplished through four 10 μm
"Mixed B" linear mixed bed GPC columns 730 supplied by Polymer
Laboratories (UK). The GPC heated column compartment 705 is operated at
145° C. to prevent precipitation when eluting from the ATREF
column 610. Sample injection amount is 500 μl. The ATREF oven 600
conditions are: temperature is from about 30 to about 110° C.;
crystallization rate of about 0.123° C./minute during a 10.75 hour
period; an elution rate of 0.123° C./minute during a 10.75 hour
period; and 14 P-TREF fractions.

[0181] The GPC 700 is calibrated in the same way as for conventional GPC
except that there is "dead volume" contained in the cross-fractionation
system due to the ATREF column 610. Providing a constant volume offset to
the collected GPC data from a given ATREF column 610 is easily
implemented using the fixed time interval that is used while the ATREF
column 620 is being loaded from the GPC sample injector 745 and
converting that (through the flow rate) to an elution volume equivalent.
The offset is necessary because during the operation of the instrument,
the GPC start time is determined by the valve at the exit end of the
ATREF column and not the GPC injector system. The presence of the ATREF
column 610 also causes some small reduction in apparent GPC column 730
efficiency. Careful construction of the ATREF columns 610 will minimize
its effect on GPC column 730 performance.

[0182] During a typical analysis, 14 individual ATREF fractions are
measured by GPC. Each ATREF fraction represents approximately a
5-7° C.-temperature "slice". The molecular weight distribution
(MWD) of each slice is calculated from the integrated GPC chromatograms.
A plot of the GPC MWDs as a function of temperature (resulting in a 3D
surface plot) depicts the overall molecular weight and crystallinity
distribution. In order to create a smoother 3D surface, the 14 fractions
are interpolated to expand the surface plot to include 40 individual GPC
chromatograms as part of the calculation process. The area of the
individual GPC chromatograms correspond to the amount eluted from the
ATREF fraction (across the 5-7° C.-temperature slice). The
individual heights of GPC chromatograms (Z-axis on the 3D plot)
correspond to the polymer weight fraction thus giving a representation of
the proportion of polymer present at that level of molecular weight and
crystallinity.

EXAMPLES

Preparation of Ethylene-Based Polymers

[0183] A continuous solution polymerization is carried out in a
computer-controlled well mixed reactor to form three ethylene-based
polyethylene polymers. The solvent is a purified mixed alkanes solvent
called ISOPAR E (ExxonMobil Chemical Co., Houston, Tex.). A feed of
ethylene, hydrogen, and polymerization catalyst are fed into a 39 gallon
(0.15 cubic meters) reactor. See Table 2 for the amounts of feed and
reactor conditions for the formation of each of the three ethylene-based
polyethylene polymers, designated Polymer (P) 1-3. "SCCM" in Table 2 is
standard cubic centimeters per minute gas flow. The catalyst for all
three of the ethylene-based polyethylene polymers is a titanium-based
constrained geometry catalyst (CGC) with the composition Titanium,
[N-(1,1-dimethylethyl)-1,1-dimethyl-1-[(1,2,3,3a,7a-η)-3-(1-pyrrolidi-
nyl)-1H-inden-1-yl]silanaminato(2-)κN][(1,2,3,4-η)-1,3-pentadien-
e]. The cocatalyst is a modified methylalumoxane (MMAO). The CGC activator
is a blend of amines, bis(hydrogenated tallow alkyl)methyl, and
tetrakis(pentafluorophenyl)borate(1-). The reactor is run liquid-full at
approximately 525 psig.

[0184] The process of polymerization is similar to the procedure detailed
in Examples 1-4 and FIG. 1 of U.S. Pat. No. 5,272,236 (Lai, et al.) and
Example 1 of U.S. Pat. No. 5,278,272 (Lai, et al.), except that a
comonomer is not used in forming P 1-3. Because no comonomer is used, P
1-3 are ethylene homopolymers. Conversion is measured as percent ethylene
conversion in the reactor. Efficiency is measured as the weight of the
polymer in kilograms produced by grams of titanium in the catalyst.

[0185] After emptying the reactor, additives (1300 ppm IRGAFOS 168, 200
ppm IRGANOX 1010, 250 ppm IRGANOX 1076, 1250 ppm calcium stearate) are
injected into each of the three ethylene-based polyethylene polymer
post-reactor solutions. Each post-reactor solution is then heated in
preparation for a two-stage devolatization. The solvent and unreacted
monomers are removed from the post-reactor solution during the
devolatization process. The resultant polymer melt is pumped to a die for
underwater pellet cutting.

[0186] Selected properties for P1-3 are provided in Table 3. P1-3 are
presented with density, melt index (I2), I10, and Brookfield
viscosity determined using the Density, Melt Index, and Brookfield
Viscosity methods, all described infra. "NM" means not measured.

[0187] Two grams of Polymer 2 (P2) are added to a 100 ml autoclave
reactor. After closing the reactor, the agitator is turned on at 1000 rpm
(revolutions per minute). The reactor is deoxygenated by pulling vacuum
on the system and pressurizing with nitrogen. This is repeated three
times. The reactor is then pressurized with ethylene up to 2000 bar while
at ambient temperatures and then vented off. This is repeated three
times. On the final ethylene vent of the reactor, the pressure is dropped
only to a pressure of about 100 bar, where the reactor heating cycle is
initiated. Upon achieving an internal temperature of ˜220°
C., the reactor is then pressurized with ethylene to about 1600 bar and
held at 220° C. for at least 30 minutes. The estimated amount of
ethylene in the reactor is approximately 46.96 grams. Ethylene is then
used to sweep 3.0 ml of a mixture of 0.5648 mmol/ml propionaldehyde and
0.01116 mmol/ml tert-butyl peroxyacetate initiator in n-heptane into the
reactor. An increase in pressure (to ˜2000 bar) in conjunction with
the addition of initiator causes the ethylene monomer to free-radical
polymerize. The polymerization leads to a temperature increase to
274° C. After allowing the reactor to continue to mix for 15
minutes, the reactor is depressurized, purged, and opened. A total of 4.9
grams of resultant ethylenic polymer, designated Example 1, is physically
recovered from the reactor (some additional product polymer is
unrecoverable due to the reactor bottom exit plugging). Based upon the
conversion value of ethylene in the reactor, the ethylenic polymer of
Example 1 comprises up to 40 weight percent ethylene-based polyethylene
P2 and the balance is highly long chain branched ethylene-based polymer
generated by free-radical polymerization.

Comparative Example 1

[0188] Free-radical polymerization of ethylene under the same process
conditions as Example 1 without the addition of an ethylene-based polymer
yields 4.9 grams of a highly long chain branched ethylene-based polymer
designated as Comparative Example 1 (CE1). A temperature increase to
285° C. occurs during the reaction.

Example 2

[0189] Two grams of Polymer 1 (P1) are added to a 100 ml autoclave
reactor. After closing the reactor, the agitator is turned on at 1000
rpm. The reactor is deoxygenated by pulling vacuum on the system and
pressurizing with nitrogen. This is repeated three times. The reactor is
then pressurized with ethylene up to 2000 bar while at ambient
temperatures and then vented off. This is repeated three times. On the
final ethylene vent of the reactor, the pressure is dropped only to a
pressure of about 100 bar, where the reactor heating cycle is initiated.
Upon achieving an internal temperature of ˜220° C., the
reactor is then pressurized with ethylene to about 1600 bar and held at
220° C. for at least 30 minutes. At this point the estimated
amount of ethylene in the reactor is approximately 46.96 grams. Ethylene
is then used to sweep 3.0 ml of a mixture of 0.5648 mmol/ml
propionaldehyde and 0.01116 mmol/ml tert-butyl peroxyacetate initiator in
n-heptane into the reactor. The increase in pressure (to ˜2000 bar)
in conjunction with the addition of initiator causes the ethylene to
free-radical polymerize. The polymerization leads to a temperature
increase to 267° C. After allowing the reactor to continue to mix
for 15 minutes, the reactor is depressurized, purged, and opened. A total
of 7.4 grams of resultant ethylenic polymer, designated Example 2, is
physically recovered from the reactor (some additional product polymer is
unrecoverable due to the reactor bottom exit plugging). Based upon the
conversion value of ethylene in the reactor, ethylenic polymer of Example
2 comprises approximately 27 weight percent ethylene-based polyethylene
P1 and the balance is highly long chain branched ethylene-based polymer
generated by free-radical polymerization.

Characterization of Example Ethylenic Polymers 1 and 2

[0190] Both ethylenic polymers Examples 1 and 2, highly long chain
branched ethylene-based polymer Comparative Example 1, and both
ethylene-based polymers P1 and P2 are tested using the DSC Crystallinity
method, provided infra in the Testing Methods section. The calculated
density for the Comparative Example polymer are from the use of the
Density method, provided infra in the Testing Methods section. Results of
the testing are provided in Table 4 and FIGS. 3 and 4.

[0191] Both ethylenic polymer Examples 1 and 2 have peak melting
temperature values between that of Comparative Example 1, which is highly
long chain branched ethylene-based polymer made under the same base
conditions as Examples 1 and 2, and each of their respective
ethylene-based polyethylene Polymers 2 and 1. Table 4 shows the highest
peak melting temperatures, Tm, of the Examples are higher by about 7
to 11° C. and have a greater amount of crystallinity, about 5 to 6
percent, versus Comparative Example 1. Additionally, the peak
crystallization temperatures, Te, are about 9 to 12° C.
higher than Comparative Example 1, indicating additional benefits in
terms of the ability to cool or solidify at a higher temperature than
CE1. The DSC Crystallinity results indicate that the ethylenic polymer
Examples 1 and 2 have both higher peak melting temperatures and peak
crystallization temperatures as well as different heats of fusion values
than the comparative example highly long chain branched ethylene-based
polymer (Comparative Example 1). Additionally, Examples 1 and 2 also
differ in some properties from P2 and P1, especially the heat of fusion
value. This strongly indicates that Examples 1 and 2 are different from
their respective highly long chain branched ethylene-based polymer and
ethylene-based polymer components.

[0192] FIGS. 3 and 4 show the heat flow versus temperature plots for the
ethylenic polymer Examples. Also shown in these figures are the heat flow
versus temperature plots for the respective ethylene-based polyethylene
P2 and P1 and Comparative Example 1.

[0194] The higher crystallinity of Example 1 relative to Comparative
Example 1 is shown by the ATREF plot given in FIG. 5. As shown in FIG. 5,
Example 1 has higher temperature melting fractions than Comparative
Example 1, the highly branched ethylene-based polymer. More importantly,
the ATREF distribution curve of Example 1 shows a relatively homogeneous
curve, indicating a generally monomodal crystallinity distribution. If
ethylenic polymer Example 1 is merely a blend of separate components, it
could be expected to show a bimodal curve of two blended polymer
components. Table 5 also shows that Example 1 has a portion of the
polymer which would elute at temperatures at or above 90° C.
Comparative Example 1 does not have a portion that elutes at or above
90° C.

[0195] The plot of FIG. 6 shows the ATREF plots of Example 2, Polymer 1,
and Comparative Example 1. In comparing the three plots, it is apparent
that Example 2 is different than both the highly long chain branched
ethylene-based polymer (CE1) and the ethylene-based polymer (P1), and not
a mere blend. Comparative Example 1 has no elution above 90° C. P1
has a significant amount of material eluting in the 90° C. or
above temperature fraction (85.2%), indicating a predominance of the high
crystallinity ethylene-based polymer fraction. Example 2, similar to
Example 1, shows a relatively homogeneous curve, indicating a relatively
narrow crystallinity distribution.

[0196] Additionally, a physical blend of an 80:20 weight ratio CE1:P1
composition is compared against ethylenic polymer Example 2 in FIG. 6.
The 80:20 weight ratio physical blend is created to compare to the
estimated 27 weight percent ethylene-based polymer P1 and balance highly
long chain branched ethylene-based polymer composition that comprises
Example 2, as stated previously in the Preparation of Example Ethylenic
Polymers 1 and 2 section. The ATREF distribution in FIG. 6 shows the
80:20 weight ratio blend has a well resolved bimodal distribution since
it is made as a blend of two distinct polymers. As previously observed,
ethylenic polymer Example 2 does not have a bimodal distribution.
Additionally, as shown in Table 5, ethylenic polymer Example 2 has a
small amount of material eluting in the 90° C. or above
temperature fraction (5.3%), whereas the 80:20 weight ratio physical
blend has an amount of elution (17.9%) reflective of its high
crystallinity ethylene-based polymer fraction.

[0198] From Table 6 it can be seen that both Examples 1 and 2 show a
narrower molecular weight distribution, Mw/Mn ratio, by
conventional GPC than that of the highly long chain branched
ethylene-based polymer Comparative Example 1 (5.03 for the control; 4.32
for Example 1; and 4.63 for Example 2). The narrower Mw/Mn
ratio of both Examples can provide benefits in physical properties,
improved clarity, and reduced haze over the Comparative Example 1 for
film applications. The Mz/Mw ratio from absolute GPC also
distinguishes the ethylenic polymer Examples with narrower values (5.89
and 3.39) and Comparative Example 1 (7.26). The lower Mz/Mw
ratio is associated with improved clarity when used in films. The
Mw(abs)/Mw(GPC) ratio shows that the Examples have lower values
(1.26, 1.29) than the Comparative Example 1 (1.51).

[0199] In Table 6, branching analysis using both g' and gpcBR are also
included. The g' value is determined by using the g' by 3D-GPC method,
provided infra in the Testing Methods section. The gpcBR value is
determined by using the gpcBR Branching Index by 3D-GPC method, provided
infra in the Testing Methods section. The lower gpcBR values for the two
ethylenic Examples as compared to Comparative Example 1 and Example 2
indicate comparatively less long chain branching; however, compared to a
1 MI metallocene polymer, there is significant long chain branching in
all the compositions.

Preparation of Example Ethylenic Polymers 3-5

Examples 3-5

[0200] This procedure is repeated for each Example. For each example, 2
grams of resin of one of the ethylene-based polymers created in the
Preparation of Ethylene-Based Polymers (that is, P1-3) are added to a 100
ml autoclave reactor. Example 3 is comprised of P2. Example 4 is
comprised of P1. Example 5 is comprised of P3. The base properties of
these polymers may be seen in Table 3. After closing the reactor, the
agitator is turned on at 1000 rpm. The reactor is deoxygenated by pulling
vacuum on the system, heating the reactor to 70° C. for one hour,
and then flushing the system with nitrogen. After this, the reactor is
pressurized with nitrogen and vacuum is pulled on the reactor. This step
is repeated three times. The reactor is pressurized with ethylene up to
2000 bar while at ambient temperatures and vented off. This step is
repeated three times. On the final ethylene vent, the pressure is dropped
only to a pressure of about 100 bar and reactor heating is initiated.
When the internal temperature reaches about 220° C., the reactor
is then pressurized with ethylene to about 1600 bar and held at
220° C. for at least 30 minutes. The estimated amount of ethylene
in the reactor is 46.53 grams. Ethylene is then used to sweep 3.9 ml of a
mixture of 0.4321 mmol/ml propionaldehyde and 0.0008645 mmol/ml
tert-butyl peroxyacetate initiator in n-heptane into the reactor. Upon
sweeping the initiator into the reactor, the pressure is increased within
the reactor to about 2000 bar, where free-radical polymerization is
initiated. A temperature rise of the reactor to 240° C. is noted.
After mixing for 15 minutes, the valve at the bottom of the reactor is
opened and the pressure is lowered to between 50-100 bar to begin
recovering the resultant polymer. Then the reactor is repressurized to
1600 bar, stirred for 3 minutes, and then the valve at the bottom is
opened to again lower the pressure to between 50-100 bar. For each
Example, a total of about 6 grams of product polymer is recovered from
the reactor. Based upon the conversion value of ethylene in the reactor,
each Example is comprised of about 33% weight percent ethylene-based
polymer and about 67% weight percent highly long chain branched
ethylene-based polymer formed during the free radical polymerization.

Comparative Example 2

[0201] Free-radical polymerization of ethylene under the same process
conditions as given in Examples 3-5 without the addition of any
ethylene-based polymer yields 4.64 grams of a highly long chain branched
ethylene-based polymer designated as Comparative Example (CE) 2. Because
no comonomer is used, Comparative Example 2 is an ethylene homopolymer. A
temperature increase during the free radical reaction to 275° C.
is noted.

Characterization of Example Ethylenic Polymers 3-5

[0202] Ethylenic polymer Examples 3-5 are tested using both the DSC
Crystallinity and Fast Temperature Rising Elution Fractionation methods,
provided infra in the Testing Methods section. The results of the testing
of Examples 3-5 are compared to similar test results of Comparative
Example 2, Polymers 1-3, and physical blends of Comparative Example 2
with Polymers 1-3. The results are shown in Table 7.

[0203] Using data from Tables 3, 4, and 7, a comparison plot between peak
melting temperature (Tm) and heat of fusion (Hf) comparing
Examples 1-5, Comparative Examples 1 and 2, and Commercial Available
Resins 1-30 can be made to find relative relationships, such as the
relationship shown in FIG. 7. Note in the case of materials with multiple
melting temperatures, the peak melting temperature is defined as the
highest melting temperature. FIG. 7 reveals that all five of the Examples
demonstrate different functional properties from the group created by the
Comparative Examples and the Commercially Available Resins.

[0204] Due to the separation between the five ethylenic polymer Examples
and the group formed from the two Comparative Examples and the
Commercially Available Resins, a line of demarcation between the groups
to emphasize the difference may be established for a given range of heats
of fusion. As shown in FIG. 7, a numerical relationship, Equations 15,
may be used to represent such a line of demarcation:

Tm(° C.)=(0.2143*Hf(J/g))+79.643 (Eq. 15).

[0205] For such a relationship line, and as can be seen in FIG. 7, all
five ethylenic polymer Examples have at least a high melting point peak
Tm equal to, if not greater than, a determined peak melting
temperature using Equation 15 for a given heat of fusion value. In
contrast, all of the Comparative Examples and Commercially Available
Resins are below the relationship line, indicating their peak melting
temperatures are less than a determined peak melting temperatures using
Equation 15 for a given heat of fusion value.

[0206] Also shown in FIG. 7, numerical relationships, Equations 16 and 17,
may also be used to represent such a line of demarcation based upon the
relationships between the Examples, Comparative Examples, and
Commercially Available Resins as just discussed:

Tm(° C.)=(0.2143*Hf(J/g))+81 (Eq. 16),

More preferably Tm(° C.)=(0.2143*Hf(J/g))+85 (Eq. 17).

[0207] Tables 4 and 7 reveal a heat of fusion range for the Example
ethylenic polymers. The heat of fusion of the ethylenic polymers are from
about 120 to about 292 J/g, preferably from about 130 to about 170 J/g.

[0208] Tables 4 and 7 also show a peak melting temperature range for the
Example ethylenic polymers. The peak melting temperature of the ethylenic
polymers are equal to or greater than about 100° C., and
preferably from about 100 to about 130° C.

[0209] Ethylenic polymer Examples 3-5, Comparative Example 2, and Polymers
1-3 are tested using the Nuclear Magnetic Resonance method, provided
infra in the Testing Methods section, to show comparative instances of
short chain branching. The results are shown in Table 8.

[0210] For Table 8, "Cx" indicates the branch length in branches/1000
total carbons (C1=methyl, C5=amyl branch, etc.). "ND" stands for a result
of none detected or observed at the given limit of detection.

[0211] Ethylene-based polymers P1-3, although tested, are not included in
the results of Table 8 because P1-3 did not exhibit C1-C6+ branching.
This is expected as P1-3 are high crystallinity ethylene-based polymers
that do not have any comonomer content that would produce short-chain
branches in the range tested.

[0212] As observed in Table 8, the ethylenic polymer Examples 3-5 show no
appreciable C1 (methyl) or C3 (propyl) branching and C2, C4, and C5
branching compared to Comparative Example 2. "Appreciable" means that the
particular branch type is not observed above the limits of detection
using the Nuclear Magnetic Resonance method (about 0.1 branches/1000
carbons), provided infra in the Testing Methods section. Comparative
Example 2, a product of free-radical branching, shows significant
branching at all ranges. In some embodiment ethylenic polymers, the
ethylenic polymer has no "appreciable" propyl branches. In some
embodiment ethylenic polymers, the ethylenic polymer has no appreciable
methyl branches. In some embodiment ethylenic polymers, at least 0.1
units of amyl groups per 1000 carbon atoms are present. In some
embodiment ethylenic polymers, no greater than 2.0 units of amyl groups
per 1000 carbon atoms are present.

[0213] Samples of Examples 3-5 are separated into subfractions using the
Preparative Temperature Rising Elution Fractionation method, provided
infra in the Testing Methods section. The subfractions are combined into
four fractions, Fractions A-D, before the solvent is removed and the
polymers are recovered. FIG. 8 represents the temperature splits for
Fractions A-D using the method on Examples 3-5.

[0214] The Fractions are analyzed for weight and their weight average
temperature determined. Table 9 summarizes the weight fraction
distribution of Examples 3-5 as well as Comparative Example 2 and gives
each Fraction its designation A-D.

[0215] As can be seen in Table 9, Examples 3-5 have a significant amount
of polymer eluting at a weight average temperature greater than
90° C. For all three ethylenic polymer Examples there is at least
one preparative TREF fraction that elutes at 90° C. or greater
(Fraction A and Fraction B). For all three ethylenic polymer Examples at
least 7.5% of the ethylenic polymer elutes at a temperature of 90°
C. or greater based upon the total weight of the ethylenic polymer
(Example 3: 22.59 wt %; Example 4: 28.29 wt %; Example 5: 25.69 wt %).
For all three ethylenic polymer Examples at least one preparative TREF
fraction elutes at 95° C. or greater (Fraction A). For all three
ethylenic polymer Examples at least 5.0% of the ethylenic polymer elutes
at a temperature of 95° C. or greater based upon the total weight
of the ethylenic polymer (Example 3: 11.27 wt %; Example 4: 15.76 wt %;
Example 5: 17.90 wt %).

[0216] Some of the Fractions are analyzed by triple detector GPC, and g'
and gpcBR values are determined using the g' by 3D-GPC and gpcBR
Branching Index by 3D-GPC methods, provided infra in the Testing Methods
section. Comparative Example 2, Polymers 1-3, and representative weight
ratio physical blends based upon the estimated composition of Examples
3-5 of respective Polymers and Comparative Example 2 are analyzed. The
results are shown in Table 10.

[0217] Table 10 show strong evidence of bonding between the ethylene-based
polymers P1-3 and the highly long chain branched ethylene-based polymer
formed in the reactor to form ethylenic polymers Examples 3-5. This can
be seen in the absolute GPC molecular weight. Comparing the molecular
weight averages from both conventional and absolute GPCs of the Examples
with their respective physical blends as listed in Table 10 show the
detected average molecular weights for the Examples are much higher than
the blends, indicating chemical bonding.

[0218] The evidence of reaction is also strongly supported by the long
chain branching indices. All the gpcBR values for the Examples show the
presence of long chain branching in the high-temperature P-TREF Fractions
(Fractions A and B), which would usually be the temperature range
reflective of high crystallinity and lack of LCBs. For ethylene-based
polymers P1-3, the gpcBR value is at or near zero since they do not have
any long chain branching. In addition, ethylene-based polymers such as
P1-3 typically give a g' index close to 1.0 and an MH exponent close to
0.72. As the level of long chain branching increases, the g' index
decreases from the value of 1.0; the MH exponent decreases from 0.72; and
the gpcBR index increases from the value of 0. Conventional highly long
chain branched ethylene-based polymer, such as CE2, does not produce a
fraction with both high crystallinity and high levels of long chain
branching.

[0219] In analyzing the samples for methyls per 1000 carbons, it is
necessary to combine Fractions into Fractions AB and CD to perform the
Methyls per 1000 Carbons Determination on P-TREF Fractions procedure,
provided infra in the Testing Methods section due to the small sample
size. Fractions A and B are combined to give Fraction AB and Fractions C
and D are combined to give Fraction CD. The new weight average
temperatures for Fractions AB and CD are calculated in accordance with
Equation 3.

[0220]FIG. 9 represents the temperature splits for combined Fractions AB
and CD of Examples 3-5. FIG. 10 and Table 11 shows the two larger
Fractions and their weight fraction as a percentage of the whole polymer.
Table 11 and FIG. 11 show the methyls per 1000 carbon results.

[0221] Examples 3-5 show relatively high levels of branching in the high
temperature fraction, Fraction AB, as indicated by the methyls per
thousand values. FIG. 11 is a plot of methyls per 1000 carbons (corrected
for end groups or methyls) versus weight average elution temperature as
determined by Methyls per 1000 Carbons Determination on P-TREF Fractions
analysis of Fractions AB and CD for Examples 3-5 using the data from
Table 11. The high temperature Fractions of the ethylenic polymer
Examples have higher than expected methyls per thousand carbons--higher
numbers than would be expected from merely a linear ethylene-based
polymer.

[0222] The results of Fast Temperature Rising Elution Fractionation
testing shown in Table 12 also indicate strong evidence of long chain
branching and grafting in Examples 3-5. This can be seen in the LS-90
measured Mw shown. Comparing the Mw of the Examples with their
respective blends, the Mw of the respective Examples are all much
higher than the respective blends.

[0223] FIGS. 13(a) and 13(b) show a 3D and 2D IR response curve,
respectively, cross fractionation result for a Polymer 3 and Comparative
Example 2 33:67 weight ratio physical blend based upon the
Cross-Fractionation by TREF method, provided infra in the Testing Methods
section. FIGS. 13(c) and 13(d) show the IR response curve using the same
method for Example 5 (which incorporates Polymer 3). FIGS. 13(a), (c),
and (d) have a z-axis (Weight Fraction) in increments of 0.02,
represented not only by grid lines (3D view only) but also by color bands
(both 3D and 2D view). The z-axis increments for Weight Fraction in FIG.
13(b) are set at 0.05 to assist in viewing the 2D representation.

[0224] Comparing the two sets of graphs, it can clearly be seen that the
blend components of FIGS. 13(a) and 13(b) are well resolved into two
distinct "islands" of temperature elution versus molecular weight,
indicating the bimodal nature of the blend. FIGS. 13(c) and 13(d) show
Example 5 and how the ethylenic polymer does not completely resolve,
indicating a single polymeric material. Also noteworthy is that the
molecular weights of the components of the blend are significantly lower
than the corresponding constituents of Example 5, which can be observed
by comparing FIG. 13(b) with FIG. 13(d).

[0225] `While the embodiments have been described with particularity, it
will be understood that various other modifications will be apparent to
and can be readily made by those skilled in the art without departing
from the spirit and scope of the invention. Accordingly, it is not
intended that the scope of the claims to be limited to the examples and
descriptions set forth but rather that the claims be construed as
encompassing all the features of patentable novelty which reside in the
present invention, including all features which would be treated as
equivalents by those skilled in the art to which the invention pertains.

[0226] It is intended that the disclosure of preferred or desired, more
preferred or more desired, highly preferred or highly desired, or most
preferred or most desired substituents, ranges, end uses, processes, or
combinations with respect to any one of the disclosed compositions and
methods is applicable as well to any other of the preceding or succeeding
embodiments of the disclosed compositions and methods, independently of
the identity of any other specific substituent, range, use, process, or
combination.

[0227] Unless otherwise stated, implicit from the context or conventional
in the art, all parts and percentages are based on weight.

[0228] All applications, publications, patents, test procedures, and other
documents cited, including priority documents, are fully incorporated by
reference to the extent such disclosure is not inconsistent with the
disclosed compositions and methods and for all jurisdictions in which
such incorporation is permitted.

[0229] Depending upon the context in which such values are described, and
unless specifically stated otherwise, such values may vary by 1 percent,
2 percent, 5 percent, or, sometimes, 10 to 20 percent. Whenever a
numerical range with a lower limit, RL, and an upper limit, RU, is
disclosed, any number falling within the range, including the limits
themselves is specifically disclosed. In particular, the following
numbers within the range are specifically disclosed: R═RL+k*(RU-RL),
wherein k is a variable ranging from 0.01 to 1.00 with a 0.01 increment,
that is, k is 0.01 or 0.02 to 0.99 or 1.00. Moreover, any numerical range
defined by two R numbers as defined is also specifically disclosed.

Patent applications by Christopher R. Eddy, Lake Jackson, TX US

Patent applications by Lonnie G. Hazlitt, Lake Jackson, TX US

Patent applications by Mehmet Demirors, Pearland, TX US

Patent applications by Pak-Meng Cham, Lake Jackson, TX US

Patent applications by Sarat Munjal, Lake Jackson, TX US

Patent applications by Teresa P. Karjala, Lake Jackson, TX US

Patent applications by Wallace W. Yau, Pearland, TX US

Patent applications by DOW GLOBAL TECHNOLOGIES LLC

Patent applications in class Utilizing an apparatus with two or more physically distinct zones

Patent applications in all subclasses Utilizing an apparatus with two or more physically distinct zones